ﺇﺫﻥ ﻤﻥ ) (1ﻭ ) (2ﻴﻨﺘﺞ : (2) ... ﻭ ﻋﻠﻴﻪ f ′ (1) = 1 : f ′ ( t ) = 1 t. lim ln (1 + )x =1 : ﺒﺎﻟﺘﺎﻟﻲ ﻭ lim ln (1 + )h = 1 x→0 x h→0 h هـ( ﺠﺩﻭل ﺘﻐﻴﺭﺍﺕ ﺍﻟﺩﺍﻟﺔ x lnx :x0 ∞+)f ′(x +∞f ( x) + ∞− ﻤﻥ ﺠﺩﻭل ﺍﻟﺘﻐﻴﺭﺍﺕ ﻨﻼﺤﻅ ﺃﻨﻪ ﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩﺍﻥ aﻭ bﻤﻥ ∞] [0; + ﻟﺩﻴﻨﺎ lna = lnb :ﺘﻜﺎﻓﺊ a = b؛ lna > lnbﺘﻜﺎﻓﺊ a > b lna < lnbﺘﻜﺎﻓﺊ a < bﻭﻋﻠﻴﻪ :ﻤﻥ ﺃﺠل lnx > 0 : x > 1؛ ﻤﻥ ﺃﺠل lnx < 0 : 0 < x < 1 xﻋﻨﺩ ﻜل ﻤﻥ : ﻭ( ﺍﻟﺘﻤﺜﻴل ﺍﻟﺒﻴﺎﻨﻲ ﻟﻠﺩﺍﻟﺔ x lnx : ﻤﻌﺎﺩﻟﺘﻲ ﺍﻟﻤﻤﺎﺴﻴﻥ ﻟﻤﻨﺤﻨﻰ ﺍﻟﺩﺍﻟﺔ lnx ) c (1;0ﻭ ) D (e;1ﻫﻤﺎ : -ﻋﻨﺩ ) y = 1( x − 1) + 0 : c (1;0ﺃﻱ y = x − 1 : y = 1 x ﺇﺫﻥ : =y 1 × ( x − e ) + 1 : )D (e;1 -ﻋﻨﺩ e e
yy = ex 0,5 0 0,5 x y = lnx ﻤﻼﺤﻅﺔ : ﻨﻼﺤﻅ ﺃﻥ ﺍﻟﺘﻤﺜﻴﻠﻴﻥ ﺍﻟﺒﻴﺎﻨﻴﻴﻥ ﻟﻜل ﻤﻥ ﺍﻟﺩﺍﻟﺘﻴﻥ x lnx :ﻭ x e xﻤﺘﻨﺎﻅﺭﺘﻴﻥ ﺒﺎﻟﻨﺴﺒﺔ ﻟﻠﻤﺴﺘﻘﻴﻡ ﺍﻟﺫﻱ ﻤﻌﺎﺩﻟﺘﻪ y = x :ﻭ ﻨﻘﻭل ﺃﻨﻬﻤﺎ ﺩﺍﻟﺘﺎﻥ ﻋﻜﺴﻴﺘﺎﻥ . x → )u′( x ﻭ( ﺍﻟﺩﻭﺍل ﺍﻷﺼﻠﻴﺔ ﻟﻠﺩﻭﺍل ﻤﻥ ﺍﻟﺸﻜل : )u( xﻟﺘﻜﻥ uﺩﺍﻟﺔ ﻗﺎﺒﻠﺔ ﻟﻼﺸﺘﻘﺎﻕ ﻋﻠﻰ ﻤﺠﺎل Iﻭ ﻟﻬﺎ ﻨﻔﺱ ﺍﻹﺸﺎﺭﺓ ﻤﻊ u′ﻓﻲ ﻫﺫﺍ ﺍﻟﻤﺠﺎل .ﺭﺃﻴﻨﺎ ﺃﻥ ﺍﻟﺩﺍﻟﺔ ﺍﻟﻤﺸﺘﻘﺔ ﻟﻠﺩﺍﻟﺔx ln u( x) : ﻟﻠﺩﺍﻟﺔ : ﻭ ﻋﻠﻴﻪ ﻴﻨﺘﺞ ﺃﻥ ﺍﻟﺩﻭﺍل ﺍﻷﺼﻠﻴﺔ →x )u′ ( x ﻋﻠﻰ Iﻫﻲ ﺍﻟﺩﺍﻟﺔ: )u( x x ﻋﻠﻰ Iﻫﻲ ﺍﻟﺩﻭﺍلln u ( x ) + λ : x → )u′( x )u( x
ﺤﻴﺙ . λ ∈ : xﻋﻠﻰ ﺍﻟﻤﺠﺎل [∞ ]3;+ﻭﻋﻠﻰ ﺍﻟﻤﺠﺎل []−∞ ; 3 ﻤﺜﺎل : 2x ﺍﻟﺩﻭﺍل ﺍﻷﺼﻠﻴﺔ ﻟﻠﺩﻭﺍل x2 − 9ﻭ ﻋﻠﻰ ﺍﻟﻤﺠﺎل −3 ; 3ﻫﻲ ﺍﻟﺩﻭﺍل x ln x2 − 9 + λ : λ ∈ ] [: ﺍﻟﺘﺯﺍﻴﺩ ﺍﻟﻤﻘﺎﺭﻥ : ﺭﺃﻴﻨﺎ ﻓﻴﻤﺎ ﺴﺒﻕ ﺃﻨﻪ ﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩ ﺤﻘﻴﻘﻲ ﻤﻭﺠﺏ ﺘﻤﺎﻤﺎ x ﻓﺈﻥ e x ≥ x :ﻭ x ≥ lnxﻭﻋﻠﻴﻪ lnx ≤ x ≤ e x : ﻨﻨﺸﺊ ﺍﻟﺘﻤﺜﻴﻼﺕ ﺍﻟﺒﻴﺎﻨﻴﺔ ﻟﻜل ﻤﻥ ﺍﻟﺩﻭﺍل ﺍﻟﺘﺎﻟﻴﺔ :x e x , x lnx , x x3 , x x2 , x x y 32,521,510,5-1,5 -1 -0,5 0 0,5 1 1,5 2 x -0,5 ﻨﻼﺤﻅ ﺃﻥ ﻨﻬﺎﻴﺔ ﻜل ﻤﻥ ﻫﺫﻩ ﺍﻟﺩﻭﺍل ﻫﻲ ∞ +ﻋﻨﺩﻤﺎ ∞، x → + ﻟﻜﻥ ﺴﻠﻭﻜﻬﺎ ﻤﺨﺘﻠﻑ .ﻭ ﻤﻨﻪ ﻨﺴﺘﻨﺘﺞ ﺍﻟﺘﺯﺍﻴﺩ ﺍﻟﻤﻘﺎﺭﻥ ﻟﻬﺎ :ﻓﻲ ﺍﻟﻼﻨﻬﺎﻴﺔ ﺘﺘﻔﻭﻕ ﺍﻟﺩﺍﻟﺔ ﺍﻷﺴﻴﺔ ﻋﻠﻲ ﺍﻟﺩﺍﻟﺔ \" ﻗﻭﺓ \" ﻋﻠﻰ ﺍﻟﺩﺍﻟﺔ ﺍﻟﻠﻭﻏﺎﺭﻴﺘﻡ .
: ﺤﺴﺎﺏ ﺒﻌﺽ ﺍﻟﻨﻬﺎﻴﺎﺕ- lim lnx = 0, n ∈ ∗ • xn x→+∞ : ﺍﻟﺒﺭﻫﺎﻥ lim lnx = 0 ﻟﺩﻴﻨﺎn = 1 ﻤﻥ ﺃﺠل x x→+∞ lim lnx = lim lnx × 1 =0 : n≥2 ﻭ ﻤﻥ ﺃﺠل xn x x n−1 x→+∞ x → +∞ lim ex = +∞, n∈ ∗ • xn x→+∞ : ﺍﻟﺒﺭﻫﺎﻥ lim e x = +∞ ﻟﺩﻴﻨﺎ n=1 ﻤﻥ ﺃﺠل xx → +∞ lim ex : ﻟﻨﺤﺴﺏ :n≥ 2 ﻭ ﻤﻥ ﺃﺠل xn x → +∞:ﻭ ﻋﻠﻴﻪ lnt = x − nlnx : ﺃﻱ ﺃﻥ lnt = lne x − lnxn : ﻓﻨﺠﺩ t = ex : ﺒﻭﻀﻊ xn lnt = x 1 − n lnx x lim x 1 − n lnx = +∞ : ﻟﺩﻴﻨﺎ x x→+∞ lim ex =+ ∞ : ﺃﻱ ﺃﻨﻪ t → +∞ : ﻭ ﻋﻠﻴﻪ lnt → +∞ : ﻭ ﻤﻨﻪ xn x → +∞ lim xnlnx = 0 , n ∈ ∗ • x→0 x>0 : ﺍﻟﺒﺭﻫﺎﻥ lim x lnx =0 : ﻟﺩﻴﻨﺎ n=1 ﺃﺠل ﻤﻥ x→0 x>0 lim xnlnx = lim xn−1 .xlnx = 0 : ﻟﺩﻴﻨﺎ: n ≥ 2 ﻭ ﻤﻥ ﺃﺠل x→0 x→0 x>0 x>0
lim xn .e x = 0 , n ∈ ∗ • x→−∞ lny = ln xn .e x : ﻨﺠﺩy = xn .e x ﺒﻭﻀﻊlny = nln x + x : ﻭ ﺒﺎﻟﺘﺎﻟﻲlny = ln xn + lne x : ﻭ ﻋﻠﻴﻪx<0 ﺃﺠل ﻤﻥ lny = − x n ln (− x ) − 1 : ﻭ ﻋﻠﻴﻪ −xlny → −∞ : ﻭﻋﻠﻴﻪ lim − x n ln (−x ) − 1 = −∞ :ﺇﺫﻥ x→−∞ −xlim x x .e x = 0 : ﻭﻤﻨﻪ lim xn .e x =0 : ﺇﺫﻥ y→0 : ﻭﻤﻨﻪx → −∞ x → −∞ y>0
– IIﺍﻟﺩﺍﻟﺔ ﺍﻟﻠﻭﻏﺎﺭﻴﺘﻤﻴﺔ ﺍﻟﻌﺸﺭﻴﺔ : -1ﺘﻌﺭﻴﻑ : ﻨﺴﻤﻰ ﺍﻟﺩﺍﻟﺔ ﺍﻟﻠﻭﻏﺎﺭﻴﺘﻤﻴﺔ ﺍﻟﻌﺸﺭﻴﺔ ﺍﻟﺩﺍﻟﺔ ﺍﻟﺘﻲ ﻨﺭﻤﺯ ﺇﻟﻴﻬﺎ ﺒﺎﻟﺭﻤﺯ log = log x lnx ﻜﻤﺎ ﻴﻠﻲ : [∞]0; + ﻭ ﺍﻟﻤﻌﺭﻓﺔ ﻋﻠﻰ ﺍﻟﻤﺠﺎل ln10 log10 = 1 (2 -2ﻨﺘﺎﺌﺞ : log1 = 0 (1 (3ﺍﻟﺩﺍﻟﺔ x log xﻤﻌﺭﻓﺔ ﻭ ﻤﺘﺯﺍﻴﺩﺓ ﺘﻤﺎﻤﺎ ﻋﻠﻰ ﺍﻟﻤﺠﺎل ∞] [0; + ﺍﻟﺒﺭﻫﺎﻥ : log 10 = ln10 = 1 • log 1 = ln1 = 0 • ln10 ln10 log x = 1 .lnx ﻟﺩﻴﻨﺎ : ln10 x 1 . 1 ﻫﻲ ﺍﻟﺩﺍﻟﺔ x ﻭﻋﻠﻴﻪ ﺍﻟﺩﺍﻟﺔ ﺍﻟﻤﺸﺘﻘﺔ ﻟﻠﺩﺍﻟﺔ log x ln10 x 1 . 1 > 0 ﻓﺈﻥ ﻭ ln10 > 0 x>0 ﻭﺒﻤﺎ ﺃﻥ ln10 x ﻭﻤﻨﻪ ﺍﻟﺩﺍﻟﺔ x log xﻤﺘﺯﺍﻴﺩﺓ ﺘﻤﺎﻤﺎ ﻋﻠﻰ ∞] [0;+ -3ﺨﻭﺍﺹ : ﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩﺍﻥ ﺤﻘﻴﻘﻴﺎﻥ aﻭ bﻤﻥ ∞] [0;+• log 1 = − log b ﻭﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩ ﻨﺎﻁﻕ rﻟﺩﻴﻨﺎ : b • log (a × b) = log a + log b• log ar = r log a • log a = log a − log b b ﺍﻟﺒﺭﻫﺎﻥ :
• log ( a × b) = ln ( a × b) = lna + lnb = lna + lnb = log a + log b ln10 ln10 ln10 ln10 1 ln 1 −lnb b b ln10 • log = = = − log b ln10• log a = log a × 1 = log a + log 1 = log a − log b b b b • log ar = lnar = r lna = r log a ln10 ln10 : x → log x ﺍﻟﺘﻤﺜﻴل ﺍﻟﺒﻴﺎﻨﻲ ﻟﻠﺩﺍﻟﺔ-6 y 2 1 -1 0 1 2 3 4 5x -1 -2
ﺘﻜﻨﻭﻟﻭﺠﻴﺎ ﺍﻹﻋﻼﻡ ﻭ ﺍﻻﺘﺼﺎل ﺍﻟﺘﻁﺒﻴﻕ :). y (1ﺒﺎﺴﺘﻌﻤﺎل ﻁﺭﻴﻘﺔ y cﻤﻊ ﺍﻟﺸﺭﻁ 0 1 ﺃﻨﺸﺊ ﺘﻤﺜﻴﻼ ﺘﻘﺭﻴﺒﻴﺎ ﻟﺤل ﺍﻟﻤﻌﺎﺩﻟﺔ ﺍﻟﺘﻔﺎﻀﻠﻴﺔ x Eulerﺒﻤﺠﺩﻭل Excelﻓﻲ ﺍﻟﻤﺠﺎل 0;bﻭﺍﻟﺨﻁﻭﺓ @ @. h 0.005 ﺍﻟﺤل : ﻟﺩﻴﻨﺎ 'y | f c(x ).'x :ﻭﻤﻨﻪ f (x h ) f (x ) | f c(x ).hﺃﻭ f (x h) f (x) | f c(x).hﻤﻊ h ! 0 f (x h) | f (x) f c(x).hﺃﻭ f (x h) | f (x) f c(x).hf (x )h | f (x ) h ﻓﻨﺤﺼل ﻋﻠﻰ )f c(x 1 y cﻓﺈﻥ 1 x x ﻭﺒﻤﺎ ﺃﻥ x . f (x )h | f )(x h ﺃﻭ xﻗﻴﻡ ﺍﻟﺩﺍﻟﺔ )ﺍﻟﺤل( ﻤﻥ ﺃﺠل x t 1ﻭﺘﻌﻁﻲ f (x )h | )f(x h ﺍﻷﻭﻟﻰ ﺒﺎﻟﻌﺒﺎﺭﺓ ﻨﺘﺤﺼل xﺍﻟﻌﺒﺎﺭﺓ ﺍﻟﺜﺎﻨﻴﺔ f (x h) | f (x) f c(x).hﻗﻴﻡ ﺍﻟﺩﺍﻟﺔ )ﺍﻟﺤل( ﻤﻥ ﺃﺠل ﺍﻟﻘﻴﻡ0 ≺ x d 1 ﻭﺫﻟﻙ ﺒﺎﻋﺘﺒﺎﺭ f (1) 0ﻓﻲ ﺍﻻﻨﻁﻼﻗﺔ ﻭﺠﻌل hﺼﻐﻴﺭﺍ ﺒﺎﻟﻘﺩﺭ ﺍﻟﺫﻱ ﻴﻀﻤﻥ ﺘﻘﺭﻴﺒﺎ ﺠﻴﺩﺍ. ﻨﺴﺘﺨﺩﻡ ﻤﺠﺩﻭل Excelﻟﻤﻘﺎﺭﺒﺔ ﺍﻟﺘﻤﺜﻴل ﺍﻟﺒﻴﺎﻨﻲ ﻟﻠﺩﺍﻟﺔ ﺍﻟﺤل . ﺤﺠﺯ ﺍﻷﻋﺩﺍﺩ :ﻨﺤﺠﺯ ﺍﻟﺨﻁﻭﺓ hﻓﻲ ﺍﻟﺨﺎﻨﺔ A3ﻤﺜﻼ.ﻤﻥ ﺃﺠل : 0 ≺ X d 1ﻨﺤﺠﺯ ﻓﻲ ﺍﻟﺨﺎﻨﺔ A4ﻗﻴﻤﺔ ﺇﺒﺘﺩﺍﺌﻴﺔ ﻟﻠﻤﺘﻐﻴﺭ ﻭﻫﻲ 1ﻨﺤﺠﺯ ﻓﻲ ﺍﻟﺨﺎﻨﺔ A5ﺍﻟﻘﺎﻋﺩﺓ x hﺍﻟﺘﻲ ﺘﻌﻁﻲ ﻗﻴﻡ ﺍﻟﻤﺘﻐﻴﺭ xﺍﻟﺘﻲ ﻫﻲ ﻗﺒل 1ﺒﻁﺭﺡ ﺍﻟﺨﻁﻭﺓ ﻓﻲ ﻜل ﻤﺭﺓﺤﺘﻰ ﺍﻟﺤﺼﻭل ﻋﻠﻰ ﻗﻴﻤﺔ ﻗﺭﻴﺒﺔ ﻤﻥ 0ﻓﻨﺤﺠﺯ A4 A$3 :ﺜﻡ ﻨﻌﻤﻡ ﻋﻠﻰ ﺒﺎﻗﻲ ﺍﻟﺨﺎﻨﺎﺕ ﻤﻥ ﻋﻤﻭﺩ Aﺇﻟﻰ ﻏﺎﻴﺔ ﺍﻟﺤﺼﻭل ﻋﻠﻰ ﻗﻴﻤﺔ ﻗﺭﻴﺒﺔ ﻤﻥ . 0 ﻨﺤﺠﺯ ﻓﻲ ﺍﻟﺨﺎﻨﺔ B4ﺍﻟﻌﺩﺩ 0ﻭﻫﻭ ﻗﻴﻤﺔ ﺍﻟﺩﺍﻟﺔ ﻤﻥ ﺃﺠل 1ﻷﻥ f (1) 0 ﻨﺤﺠﺯ ﻓﻲ ﺍﻟﺨﺎﻨﺔ B5ﺍﻟﻘﻴﻤﺔ ﺍﻟﺘﻘﺭﻴﺒﻴﺔ ﻟﻠﻌﺩﺩ ) y f (x hﻭﻟﺩﻴﻨﺎ f (x h) | f (x) f c(x).hﻓﻨﺤﺠﺯ B4 $A$3 / A4 :ﺜﻡ ﻨﻌﻤﻡ ﻋﻠﻰ ﺒﺎﻗﻲ ﺍﻟﺨﺎﻨﺎﺕ ﻤﻥ ﻋﻤﻭﺩ Bﺤﺘﻰ ﺍﻟﻭﺼﻭل ﺇﻟﻰ ﺁﺨﺭ ﻗﻴﻤﺔ ﻟﻠﻤﺘﻐﻴﺭ ﻤﻥ ﺍﻟﻌﻤﻭﺩ . A
ﻤﻥ ﺃﺠل : X t 1ﻨﺤﺠﺯ ﻓﻲ ﺍﻟﺨﺎﻨﺔ C 4ﻗﻴﻤﺔ ﺍﺒﺘﺩﺍﺌﻴﺔ ﻟﻠﻤﺘﻐﻴﺭ ﻭﻫﻲ 1ﻨﺤﺠﺯ ﻓﻲ ﺍﻟﺨﺎﻨﺔ C5ﺍﻟﻘﺎﻋﺩﺓ x hﺍﻟﺘﻲ ﺘﻌﻁﻲ ﻗﻴﻡ ﺍﻟﻤﺘﻐﻴﺭ xﺍﻟﺘﻲ ﻫﻲ ﺒﻌﺩ 1ﺒﺈﻀﺎﻓﺔ ﺍﻟﺨﻁﻭﺓﻓﻲ ﻜل ﻤﺭﺓ ﻓﻨﺤﺠﺯ C4 A$3 :ﺜﻡ ﻨﻌﻤﻡ ﻋﻠﻰ ﺒﺎﻗﻲ ﺍﻟﺨﺎﻨﺎﺕ ﻤﻥ ﻋﻤﻭﺩ Cﺇﻟﻰ ﻏﺎﻴﺔ ﺁﺨﺭ ﻗﻴﻤﺔ ﻟﻠﻤﺘﻐﻴﺭ ﻤﻥ ﺍﻟﻌﻤﻭﺩ . B ﻨﺤﺠﺯ ﻓﻲ ﺍﻟﺨﺎﻨﺔ D4ﺍﻟﻌﺩﺩ 0ﻭﻫﻭ ﻗﻴﻤﺔ ﺍﻟﺩﺍﻟﺔ ﻤﻥ ﺃﺠل 1ﻷﻥ f (1) 0 ﻨﺤﺠﺯ ﻓﻲ ﺍﻟﺨﺎﻨﺔ D5ﺍﻟﻘﻴﻤﺔ ﺍﻟﺘﻘﺭﻴﺒﻴﺔ ﻟﻠﻌﺩﺩ ) y f (x hﻭﻟﺩﻴﻨﺎ f (x h) | f (x) f c(x).hﻓﻨﺤﺠﺯ D4 $A$3 / C4ﺜﻡ ﻨﻌﻤﻡ ﻋﻠﻰ ﺒﺎﻗﻲ ﺍﻟﺨﺎﻨﺎﺕ ﻤﻥ ﻋﻤﻭﺩ Dﺤﺘﻰ ﺍﻟﻭﺼﻭل ﺇﻟﻰ ﺁﺨﺭ ﻗﻴﻤﺔ ﻟﻠﻤﺘﻐﻴﺭ ﻤﻥ ﺍﻟﻌﻤﻭﺩ . B ﺍﻟﺘﻤﺜﻴل ﺍﻟﺒﻴﺎﻨﻲ: ﻨﺨﺘﺎﺭ ﺍﻟﻌﻤﻭﺩﻴﻥ Aﻭ Bﻨﻀﻐﻁ ﻋﻠﻰ ﺍﻟﻤﺴﺎﻋﺩ ﺍﻟﺒﻴﺎﻨﻲ ،ﻨﻭﺍﺼل ﺍﻟﻌﻤﻠﻴﺔ ﺜﻡ ﺍﻟﻤﻨﺤﻨﻰ ﻤﻥ ﺍﻟﻨﻭﻉ ﻭﻨﺨﺘﺎﺭﻨﺠﺩ ﺍﻟﺴﻠﺴﻠﺔ ﺍﻷﻭﻟﻰ ﺜﻡ ﺍﺨﺘﻴﺎﺭ ﺍﻟﺴﻠﺴﻠﺔ ﺒﺎﻟﻀﻐﻁ ﻋﻠﻰ ﺒﺎﻟﻀﻐﻁ ﻋﻠﻰ .ﺜﻡ ﻨﻀﻐﻁ ﺍﻟﺘﻲ ﺘﺨﺹ ﺘﻤﺜﻴل ﺍﻟﺩﺍﻟﺔ )ﺍﻟﺤل( ﻋﻠﻰ ﺍﻟﻤﺠﺎل ﺍﻷﻭل 0.1ﻤﺤﺠﻭﺯﺓ ﺒﺎﺴﻡ@ @ﻹﻀﺎﻓﺔ ﺍﻟﺴﻠﺴﻠﺔ ﺍﻟﺜﺎﻨﻴﺔ ﺍﻟﺘﻲ ﺘﻌﻁﻲ ﺍﻟﺘﻤﺜﻴل ﺍﻟﺒﻴﺎﻨﻲ ﻋﻠﻰ ﺍﻟﻤﺠﺎل ﻋﻠﻰ ﺍﻟﺜﺎﻨﻲ 1;bﻜﻤﺎ ﻴﻠﻲ> >:ﻨﻀﻊ ﻤﺅﺸﺭ ﺍﻟﻜﺘﺎﺒﺔ ﻋﻠﻰ ﺨﺎﻨﺔ ﻗﻴﻡ xﺜﻡ ﻨﺤﺠﺯ ﻗﻴﻡ ﺍﻟﻌﻤﻭﺩ Cﺒﺎﻟﻀﻐﻁ ﺒﺎﻟﻔﺄﺭﺓ ﻤﻥ ﺍﻟﻘﻴﻤﺔ ﺍﻷﻭﻟﻰ ﻓﻲ C 4ﺇﻟﻰ ﺁﺨﺭ ﻗﻴﻤﺔ ﻤﻥ ﻨﻔﺱ ﺍﻟﻌﻤﻭﺩ.ﻨﻀﻊ ﻤﺅﺸﺭ ﺍﻟﻜﺘﺎﺒﺔ ﻋﻠﻰ ﺨﺎﻨﺔ ﻗﻴﻡ yﺜﻡ ﻨﺤﺠﺯ ﻗﻴﻡ ﺍﻟﻌﻤﻭﺩ Dﺒﺎﻟﻀﻐﻁ ﺒﺎﻟﻔﺄﺭﺓ ﻤﻥ ﺍﻟﻘﻴﻤﺔ ﺍﻷﻭﻟﻰ ﻓﻲ D4ﺇﻟﻰ ﺁﺨﺭ ﻗﻴﻤﺔ ﻤﻥ ﻨﻔﺱ ﺍﻟﻌﻤﻭﺩ.ﻓﻴﻅﻬﺭ ﺍﻟﻤﻨﺤﻨﻴﺎﻥ ﻤﻜﻤﻼﻥ ﻟﺒﻌﻀﻬﻤﺎ ﺒﻠﻭﻨﻴﻥ ﻤﺨﺘﻠﻔﻴﻥ ﻨﻀﻐﻁ ﺒﻌﺩﻫﺎ ﻋﻠﻰ ﺍﻟﺘﺎﻟﻲ،ﺤﻴﺙ ﻴﺸﻜﻼﻥ ﻤﻨﺤﻨﻲ ﺍﻟﺩﺍﻟﺔ )ﺍﻟﺤل( ﻋﻠﻰ ﺍﻟﻤﺠﺎل ، 0,bﺜﻡ ﺍﻹﻨﻬﺎﺀ @ @.
ﺘﻤـﺎﺭﻴﻥ ﻭ ﻤﺸﻜﻼﺕ ﺍﻟﺘﻤﺭﻴﻥ. 1 ﺃﺫﻜﺭ ﺼﺤﺔ ﺃﻡ ﺨﻁﺄ ﻜل ﺠﻤﻠﺔ ﻤﻤﺎ ﻴﻠﻲ ﻤﻊ ﺍﻟﺘﻌﻠﻴل :-1ﺍﻟﺩﺍﻟﺔ ) x ln ( − xﻤﻌﺭﻓﺔ ﻋﻠﻰ [∞]0;+ -2ﺍﻟﺩﺍﻟﺔ ) x ln ( xﻤﻌﺭﻓﺔ ﻋﻠﻰ ∗ -3ﺍﻟﺩﺍﻟﺔln x 2 :∗) ( +ﻋﻠﻰ xﻤﻌﺭﻓﺔ -4ﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩ ﻁﺒﻴﻌﻲ ﻏﻴﺭ ﻤﻌﺩﻭﻡ αﻓﺈﻥ ln 2α = lnα2 -5ﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩ ﺤﻘﻴﻘﻲ ﻤﻭﺠﺏ ﺘﻤﺎﻤﺎ ln x > 0 : x -6ﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩﺍﻥ ﺤﻘﻴﻘﻴﺎﻥ ﻤﻭﺠﺒﺎﻥ ﺘﻤﺎﻤﺎ : ln (a + b) = lna + lnb -7ﺇﺫﺍ ﻜﺎﻥ x < 1ﻓﺈﻥ ln x < 0 : xﻤﻌﺭﻑ ﻋﻠﻰ [∞]0;+ 1 -8ﺍﻟﺩﺍﻟﺔ lnx -9ﺇﺫﺍ ﻜﺎﻥ xﻋﺩﺩ ﺤﻘﻴﻘﻲ ﻏﻴﺭ ﻤﻌﺩﻭﻡ ﻓﺈﻥ elnx = x lne2008 = 2008 -10 lim x = ∞+ -11 lnx ∞x→+Lim ln ( − x ) = ∞+ -12 -13∞x→−ln ( −2)1830 = 1830ln2ﺇﺫﺍ ﻜﺎﻥ xﻋﺩﺩ ﺤﻘﻴﻘﻲ ﻏﻴﺭ ﻤﻌﺩﻭﻡ ﻓﺈﻥ lnx2 = 2ln x : -14 -15ln12 = ln 12 = ln4ln3 3
ﺍﻟﺘﻤﺭﻴﻥ. 2 ﺒﺴﻁ ﺍﻟﻌﺒﺎﺭﺍﺕ ﺍﻟﺘﺎﻟﻴﺔ :1) ln e − lne−3 2) ln e3 − ln e e2)3 1 ln25 + ln 2 4) ln2 2 − 3 ln2 5 4 2)5)ln (128)2 − ln (16× 32 6)ln243 + ln610 + ln 1 1024 ﺍﻟﺘﻤﺭﻴﻥ. 3 ﻋﻴﻥ ﺍﻟﻘﻴﻡ ﺍﻟﻤﻘﺭﺒﺔ ﻟﻸﻋﺩﺍﺩ ﺍﻵﺘﻴﺔ ﺇﻟﻰ 10−2ﺒﺎﺴﺘﻌﻤﺎل ﺁﻟﺔ ﺤﺴﺎﺒﻴﺔ : ln ( 2007)2006 ; ln (1962)1954 ; 1 ln1830 ( )( )ln 2 1418 ; ln ( 2,0005)12 ; ln 25×37×53 ﺍﻟﺘﻤﺭﻴﻥ. 4 ﺃﺩﺭﺱ ﺇﺸﺎﺭﺓ ﻜل ﻤﻥ ﺍﻷﻋﺩﺍﺩ ﺍﻵﺘﻴﺔ : a = 3ln7 − 5ln5; b = 3ln2 − 1 ln15 2 ( )c = ln 3− 2 ;d = ln3 )ln(0, 5 ﺍﻟﺘﻤﺭﻴﻥ. 5( )2ln 2 3+ 4 0 3 −1 + ln 4 = : ﺍﻟﺘﺎﻟﻴﺔ ﺍﻟﻤﺴﺎﻭﺍﺓ ﺼﺤﺔ ﻤﻥ ﺘﺤﻘﻕ
. 6ﺍﻟﺘﻤﺭﻴﻥ ﻭ ﺍﺤﺴﺏ ﺩﺍﻟﺘﻬﺎ ﺍﻟﻤﺸﺘﻘﺔ ﻓﻲ ﻜل ﺤﺎﻟﺔf ﻋﻴﻥ ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑ ﻭ ﻤﺠﻤﻭﻋﺔ ﻗﺎﺒﻠﻴﺔ ﺍﻻﺸﺘﻘﺎﻕ ﻟﻠﺩﻭﺍل 1) f (x) = 1 x2 − x + lnx : ﻤﻤﺎ ﻴﻠﻲ 2 2) f ( x) = ln ( x2 − 4) 3) f ( x) = x ln x 4) f (x) = x 1 lnx 5) f ( x) = x ln (− x) 6) f ( x ) = ln x−1 x − 2 ( )7) f ( x) = ln e2x − 5ex + 6 8) f (x) = 1 ( lnx )2 2 . 7ﺍﻟﺘﻤﺭﻴﻥ : ﺍﺤﺴﺏ ﺍﻟﻨﻬﺎﻴﺎﺕ ﺍﻟﺘﺎﻟﻴﺔ1) lim x − lnx 2)lim 1 3) lim ln x > x > lnx x2 + 1 x 0 x→+∞ x→0 →4)lim ln (lnx) 5) lim e x ( )6) lim x2 − lnx > > lnx x→+∞ x→1 x →0 7) lim lnx lnx ( lnx ) 2 xx →+∞ x4 x 8) lim 9) lim x→+∞ x→+∞10) lim ( x − lnx) lnx 11) lim x lnx 12) lim x ln 1 + 1 > > x x→0 x→0 x→+∞ : ﻜل ﻤﻥ ﺍﻟﻤﻌﺎﺩﻻﺕ ﺍﻟﺘﺎﻟﻴﺔ ﺤل ﻓﻲ. 8ﺍﻟﺘﻤﺭﻴﻥ 1) lnx − ln ( x − 2) = 1 2) lnx2 = 4 3) ln ( x − 1) + ln ( x + 2) = ln ( x2 − 3x + 2) 4) 2(lnx)2 + 5lnx − 3 = 0
)1 < lnx 1 ﺍﻟﺘﻤﺭﻴﻥ. 9 2 ﺤل ﻓﻲ ﻜل ﻤﻥ ﺍﻟﻤﺘﺭﺍﺠﺤﺎﺕ ﺍﻟﺘﺎﻟﻴﺔ : 2) ln x < 1 3) lnx + ln ( x − 1) > ln6 )4 ln ( x - )1 < 0 ln ( x + )3 5) (lnx)2 − 8lnx + 7 > 0 ( )6) x2 − 4x lnx ≥ 0 ﺍﻟﺘﻤﺭﻴﻥ. 10 ﻋﻴﻥ ﺍﻟﺩﻭﺍل ﺍﻷﺼﻠﻴﺔ gﻟﻠﺩﺍﻟﺔ fﻓﻲ ﻜل ﺤﺎﻟﺔ ﻤﻤﺎ ﻴﻠﻲ ﻋﻠﻰ ﺍﻟﻤﺠﺎل I )1 f ( )x = 3 x2 − 2 [∞; I= ]0 ; + x)2 f ( x) = −x3 + x 1 1 + ( x 1 2 [∞; I= ]1 ; + − )-1 )3 f = )(x x−1 [∞; I= ]2 ; + x2 − 2x [∞; I= ]0 ; + [ ; I= ]0 ; π )4 f = )(x (lnx) 2 [∞; I= ]-∞ ; + x )5 f ( x ) = cos x sin x )6 f ( )x = ex 1 ex + ﺍﻟﺘﻤﺭﻴﻥ. 11 fﺩﺍﻟﺔ ﻋﺩﺩﻴﺔ ﻟﻤﺘﻐﻴﺭ ﺤﻘﻴﻘﻲ xﻤﻌﺭﻓﺔ ﺒﺎﻟﻌﺒﺎﺭﺓ f ( )x = − x3 − (12 − )e) x2 − (9 − 4e x + 3e − 2 x2 + 4x + 3 : eﻴﺭﺴﻡ ﺇﻟﻰ ﺍﻟﻌﺩﺩ ﺍﻟﻨﻴﺒﻴﺭﻱ . – 1ﺒﻴﻥ ﺃﻨﻪ ﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩ ﺤﻘﻴﻘﻲ xﻤﻥ − {−3;−1} :
f )( x = ax + b+ x c 3 + d ﻓﺈﻥ : + x+1 ﺤﻴﺙ d , c, b, a :ﺃﻋﺩﺍﺩ ﺤﻘﻴﻘﻴﺔ ﻴﻁﻠﺏ ﺘﻌﻴﻴﻨﻬﺎ . – 2ﻋﻴﻥ ﺍﻟﺩﻭﺍل ﺍﻷﺼﻠﻴﺔ gﻟﻠﺩﺍﻟﺔ fﻋﻠﻰ ﺍﻟﻤﺠﺎل ∞] [−1;+ – 3ﺍﺴﺘﻨﺘﺞ ﺩﺍﻟﺔ ﺃﺼﻠﻴﺔ hﻟﻠﺩﺍﻟﺔ fﺘﺄﺨﺫ ﺍﻟﻘﻴﻤﺔ 1ﻋﻨﺩ x = 0 ﺍﻟﺘﻤﺭﻴﻥ. 12 fﺩﺍﻟﺔ ﻋﺩﺩﻴﺔ ﻟﻤﺘﻐﻴﺭ ﺤﻘﻴﻘﻲ xﻤﻌﺭﻓﺔ ﻜﻤﺎ ﻴﻠﻲ :)f ( x) = − x2 + x + 2ln ( x + 1 ;O( )→ , → c i j ﻤﺘﻌﺎﻤﺩ ﻤﺘﺠﺎﻨﺱ ﺘﻤﺜﻴﻠﻬﺎ ﺍﻟﺒﻴﺎﻨﻲ ﻓﻲ ﻤﻌﻠﻡ – 1ﺃﺩﺭﺱ ﺘﻐﻴﺭﺍﺕ ﺍﻟﺩﺍﻟﺔ fﻭ ﺍﻟﻔﺭﻭﻉ ﺍﻟﻼﻨﻬﺎﺌﻴﺔ . – 2ﻫل ﺘﻭﺠﺩ ﻤﻤﺎﺴﺎﺕ ﻟﻠﻤﻨﺤﻨﻰ cﻤﻌﺎﻤل ﺘﻭﺠﻴﻬﻬﺎ 3ﺤﻴﺙ ﻴﻁﻠﺏ) ( ﻜﺘﺎﺒﺔ ﻤﻌﺎﺩﻻﺘﻬﺎ ﻓﻲ ﺤﺎﻟﺔ ﻭﺠﻭﺩﻫﺎ .( )2 5< x0 < 2 ﺤﻴﺙ ﺘﻘﺒل ﺤﻼ ﻭﺤﻴﺩﺍ x0 f – 3ﺒﻴﻥ ﺃﻥ ﺍﻟﻤﻌﺎﺩﻟﺔ x = 0 – 4ﺃﻨﺸﺊ ﺍﻟﻤﻤﺎﺴﺎﺕ ﺫﺍﺕ ﻤﻌﺎﻤل ﺍﻟﺘﻭﺠﻴﻪ 3ﺜﻡ ﺃﻨﺸﺊ ( ). c – 5ﻨﻌﺘﺒﺭ ﺍﻟﺩﺍﻟﺔ gﺍﻟﻤﻌﺭﻓﺔ ﺒﺎﻟﻌﺒﺎﺭﺓ: )g ( x) = − x2 + x + 2ln ( x + 1 ﺃ – ﺃﺜﺒﺕ ﺃﻥ gﺩﺍﻟﺔ ﺯﻭﺠﻴﺔ . ﺏ– ﺃﻜﺘﺏ g xﺩﻭﻥ ﺭﻤﺯ ﺍﻟﻘﻴﻤﺔ ﺍﻟﻤﻁﻠﻘﺔ ( ). ﺝ– ﺃﻨﺸﺊ ﺍﻟﺘﻤﺜﻴل ﺍﻟﺒﻴﺎﻨﻲ γﻟﻠﺩﺍﻟﺔ) ( gﺍﻨﻁﻼﻗﺎ ﻤﻥ ) . (c ﺍﻟﺘﻤﺭﻴﻥ. 13 ϕ (Iﺩﺍﻟﺔ ﻤﻌﺭﻓﺔ ﻜﻤﺎ ﻴﻠﻲ ϕ ( x ) = x2 − 4 x + 3 + 6 ln x − 2 : – 1ﺍﺤﺴﺏ ) ϕ (1ﻭ ). ϕ ( 3
– 2ﺍﺩﺭﺱ ﺘﻐﻴﺭﺍﺕ ﺍﻟﺩﺍﻟﺔ . ϕ – 3ﺍﺴﺘﻨﺘﺞ ﺇﺸﺎﺭﺓ ) . ϕ ( xf ( )x = x + 2 − x 5 2 − 6 ln x − 2 ﺩﺍﻟﺔ ﻤﻌﺭﻓﺔ ﺒﺎﻟﻌﺒﺎﺭﺓ : f ( II − x−2 (1ﺒﻴﻥ ﺃﻨﻪ ﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩ ﺤﻘﻴﻘﻲ xﺤﻴﺙ x ≠ 2 f ′ ( )x = ( ϕ )(x ﻓﺈﻥ : x − 2)2 (2ﺍﺴﺘﻨﺘﺞ ﺘﻐﻴﺭﺍﺕ ﺍﻟﺩﺍﻟﺔ f ( 3ﻟﻴﻜﻥ Γﺍﻟﺘﻤﺜﻴل ﺍﻟﺒﻴﺎﻨﻲ ﻟﻠﺩﺍﻟﺔ fﻓﻲ ﺍﻟﻤﺴﺘﻭﻯ ﺍﻟﻤﻨﺴﻭﺏ ﻟﻤﻌﻠﻡ ﻤﺘﻌﺎﻤﺩ ﻤﺘﺠﺎﻨﺱ) ( ،ﺍﺩﺭﺱ ﺍﻟﻔﺭﻭﻉ ﺍﻟﻼﻨﻬﺎﺌﻴﺔ ﻟﻠﻤﻨﺤﻨﻲ ( ). Γ ;O → , → i j ( 4ﺍﺤﺴﺏ ) f ( −4) , f (4) , f (0) , f ( −1ﺒﺎﻟﺘﻘﺭﻴﺏ ﺇﻟﻰ . 10−1 ( 5ﺘﺤﻘﻕ ﺃﻥ ) w ( 2;4ﻤﺭﻜﺯ ﺘﻨﺎﻅﺭ ﻟﻠﻤﻨﺤﻨﻰ ). (Γ ( 6ﺍﺭﺴﻡ ). (Γ ﺍﻟﺘﻤﺭﻴﻥ. 14 f )(x = − xln 1 + 1 , x > 0 f x ﺤﻴﺙ : ﻨﻌﺘﺒﺭ ﺍﻟﺩﺍﻟﺔ f ( )0 = −1 ( )،;O → , → c ﻤﺘﺠﺎﻨﺱ ﻤﺘﻌﺎﻤﺩ ﻤﻌﻠﻡ ﻓﻲ ﺍﻟﺒﻴﺎﻨﻲ ﺘﻤﺜﻴﻠﻬﺎ i j ﺍﻟﻭﺤﺩﺓ )(4cm -1ﺃﺩﺭﺱ ﺍﺴﺘﻤﺭﺍﺭﻴﺔ fﻋﻨﺩ 0ﻤﻥ ﺍﻟﻴﻤﻴﻥ . -2ﺃﺩﺭﺱ ﻗﺎﺒﻠﻴﺔ ﺍﻻﺸﺘﻘﺎﻕ ﻟﻠﺩﺍﻟﺔ fﻋﻨﺩ 0ﻤﻥ ﺍﻟﻴﻤﻴﻥ .ﻤﺎ ﻫﻭ ﺍﻟﺘﻔﺴﻴﺭ ﺍﻟﻬﻨﺩﺴﻲ . -3ﺃﺤﺴﺏ ﻤﻥ ﺃﺠل f ′ ( x) : x > 0ﻭ ) f ′′ ( x ﺃﺤﺴﺏ ) lim f ′ ( xﺜﻡ ﺍﺴﺘﻨﺘﺞ ﺇﺸﺎﺭﺓ ) f ′ ( x ∞x→+ -4ﺃﺩﺭﺱ ﺘﻐﻴﺭﺍﺕ ﺍﻟﺩﺍﻟﺔ f
-5ﺃﻨﺸﺊ )(c -6ﻨﻌﺘﺒﺭ ﺍﻟﺩﺍﻟﺔ gﺤﻴﺙ g ( x ) = xf ( x ) − x : -ﺃﺤﺴﺏ g′ xﺜﻡ ﺍﺴﺘﻨﺘﺞ ﺩﺍﻟﺔ ﺃﺼﻠﻴﺔ ﻟﻠﺩﺍﻟﺔ) ( fﻋﻠﻰ ∞ ] [0 ; + ﺍﻟﺘﻤﺭﻴﻥ. 15 fﺩﺍﻟﺔ ﻋﺩﺩﻴﺔ ﻟﻤﺘﻐﻴﺭ ﺤﻘﻴﻘﻲ xﻤﻌﺭﻓﺔ ﻜﻤﺎ ﻴﻠﻲ : c ,ﺘﻤﺜﻴﻠﻬﺎ ﺍﻟﺒﻴﺎﻨﻲ ﻓﻲ ﻤﻌﻠﻡ ﻤﺘﻌﺎﻤﺩ ﻤﺘﺠﺎﻨﺱ) ( f ( )x = 2x − 11 − ln (6 − )x x − 6 ;O → → i, j -1ﺍﺩﺭﺱ ﺘﻐﻴﺭﺍﺕ ﺍﻟﺩﺍﻟﺔ f -2ﺍﻜﺘﺏ ﻤﻌﺎﺩﻟﺔ ﺍﻟﻤﻤﺎﺱ ﻟﻠﻤﻨﺤﻨﻲ cﻋﻨﺩ ﺍﻟﻨﻘﻁﺔ ﺫﺍﺕ ﺍﻟﻔﺎﺼﻠﺔ ( )0 -3ﺍﺤﺴﺏ ﺒﺘﻘﺭﻴﺏ 10−2ﺍﻷﻋﺩﺍﺩf (4) ; f ( 3) ; f (0) ; ( )f −1 : f (α ) = 0 : ﺒﺤﻴﺙ α ﺒﻴﻥ ﺃﻨﻪ ﻴﻭﺠﺩ ﻋﺩﺩ ﺤﻘﻴﻘﻲ ﻭﺤﻴﺩ -4 −1 < α < 0 f ( β ) = 0 βﺒﺤﻴﺙ ﺒﻴﻥ ﺃﻨﻪ ﻴﻭﺠﺩ ﻋﺩﺩ ﺤﻘﻴﻘﻲ ﻭﺤﻴﺩ -5 0 < β < 6 : -6ﺃﻨﺸﺊ )(c -7ﻨﺎﻗﺵ ﺒﻴﺎﻨﻴﺎ ﻭ ﺤﺴﺏ ﻗﻴﻡ ﺍﻟﻭﺴﻴﻁ ﺍﻟﺤﻘﻴﻘﻲ mﻋﺩﺩ ﻭ ﺇﺸﺎﺭﺓ ﺤﻠﻭل ﺍﻟﻤﻌﺎﺩﻟﺔ f ( x ) = m -8ﻨﺎﻗﺵ ﺒﻴﺎﻨﻴﺎ ﻋﺩﺩ ﺤﻠﻭل ﺍﻟﻤﺘﺭﺍﺠﺤﺔ ( )f x ≤ m :b; a ﺤﻴﺙ 2x − 11 = a + b -9ﺒﻴﻥ ﺃﻨﻪ ﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩ ﺤﻘﻴﻘﻲ xﻓﺈﻥ : x − 6 x−6 ﻋﺩﺩﺍﻥ ﺤﻘﻴﻘﻴﺎﻥ ﻴﻁﻠﺏ ﺘﻌﻴﻴﻨﻬﻤﺎ -10ﻨﻌﺘﺒﺭ ﺍﻟﺩﺍﻟﺔ gﺤﻴﺙ g ( x ) = ( x − 6) ln (6 − x ) + x :ﻋﻴﻥ ﺍﻟﺩﺍﻟﺔ ﺍﻟﻤﺸﺘﻘﺔ ﻟﻠﺩﺍﻟﺔ gﻋﻠﻰ ﺍﻟﻤﺠﺎل []−∞;6
-11ﺍﺴﺘﻨﺘﺞ ﺍﻟﺩﻭﺍل ﺍﻷﺼﻠﻴﺔ ﻟﺩﺍﻟﺔ fﻋﻠﻰ ﺍﻟﻤﺠﺎل ] [−∞;6 ﺍﻟﺘﻤﺭﻴﻥ. 16ﻀﻊ ﺍﻟﻌﻼﻤﺔ √ﺃﻤﺎﻡ ﻜل ﺠﻤﻠﺔ ﺼﺤﻴﺤﺔ ﻭ ﺍﻟﻌﻼﻤﺔ ×ﺃﻤﺎﻡ ﻜل ﺠﻤﻠﺔ ﺨﺎﻁﺌﺔ : ∈x ∗ ; log x = 1 logx -1 + 2 loge = 1 -2 ln10 log2n = ln2n -3 n ∈ ; log10n = n -4( ). 109 < log 9, 26.109 < 1010 -5 ∈a ∗ ; log 1 = 1 -6 + a loga lim logx = ∞+ -7 x ∞x→+ ∈x ∗ ; (logx)2 = 2logx -8 +. ∈n ∗ }{1 ; logn 10 n = 1 -9 − n xﻋﻠﻰ [∞. ]0;+ 1 ﻫﻲ ﺍﻟﺩﺍﻟﺔ x -10ﻤﺸﺘﻘﺔ ﺍﻟﺩﺍﻟﺔ logx x ﺍﻟﺘﻤﺭﻴﻥ. 17 ﺤل ﻓﻲ ﺍﻟﻤﻌﺎﺩﻻﺕ ﻭ ﺍﻟﻤﺘﺭﺍﺠﺤﺎﺕ ﺍﻟﺘﺎﻟﻴﺔ : logx + log ( x − 1) = log6 ( 1 2(log x)2 + 5logx − 3 = 0 ( 2 logx > 3 ( 4 log ( x − 6) > 2logx ( 5
ﺍﻟﺘﻤﺭﻴﻥ. 18 ﺍﺤﺴﺏ ﺍﻟﻤﺠﻤﻭﻉ :S = log 1 +log 2 +log 3 + . . . +log 98 +log 99 2 3 4 99 100 ﺍﻟﺘﻤﺭﻴﻥ. 19 ﻋﻴﻥ ﻤﺠﻤﻭﻋﺔ ﺘﻌﺭﻴﻑ ﻜل ﺩﺍﻟﺔ ﻤﻤﺎ ﻴﻠﻲ ﺜﻡ ﺃﺤﺴﺏ ﺍﻟﻨﻬﺎﻴﺎﺕ ﻋﻨﺩ ﺃﻁﺭﺍﻓﻬﺎ : f ( x) = x + log x (1 ( )f ( x) = x2 − 1 − log x2 − 1 ( 2 f ( )x = 1 −1 (3 logx f ( x) = (logx)2 (4 ﺍﻟﺘﻤﺭﻴﻥ. 20 ﻨﻌﺘﺒﺭ ﺍﻟﺩﺍﻟﺔ fﺫﺍﺕ ﺍﻟﻤﺘﻐﻴﺭ ﺍﻟﺤﻘﻴﻘﻲ xﺤﻴﺙ f ( x ) = log x − 1 : ﺍﻟﻤﻤﺜل ﻟﺘﻐﻴﺭﺍﺕ -1ﺍﺩﺭﺱ ﺘﻐﻴﺭﺍﺕ ﺍﻟﺩﺍﻟﺔ . f -2ﺍﺩﺭﺱ ﺍﻟﻔﺭﻭﻉ ﺍﻟﻼﻨﻬﺎﺌﻴﺔ ﻭ ﺍﻟﻤﺴﺘﻘﻴﻤﺎﺕ ﺍﻟﻤﻘﺎﺭﺒﺔ ﻟﻠﻤﻨﺤﻨﻰ ( )C fﻓﻲ ﻤﻌﻠﻡ ﻤﺘﻌﺎﻤﺩ ﻤﺘﺠﺎﻨﺱ . -3ﺍﻜﺘﺏ ﻤﻌﺎﺩﻟﺔ ﺍﻟﻤﻤﺎﺱ ﻟﻠﻤﻨﺤﻨﻰ Cﻓﻲ ﺍﻟﻨﻘﻁﺔ ﺫﺍﺕ ﺍﻟﻔﺎﺼﻠﺔ ( )2 -4ﻫل ﺘﻭﺠﺩ ﻤﻤﺎﺴﺎﺕ ﻟﻠﻤﻨﺤﻨﻰ Cﻴﻜﻭﻥ ﻤﻌﺎﻤل ﺘﻭﺠﻴﻬﻬﺎ ﻤﺴﺎﻭﻴﺎ) ( ﺇﻟﻰ . 10 -5ﺃﻨﺸﺊ Cﺒﻌﺩ ﺘﻌﻴﻴﻥ ﻨﻘﻁ ﺘﻘﺎﻁﻊ Cﻤﻊ ﺍﻟﻤﺤﺎﻭﺭ ﺍﻹﺤﺩﺍﺜﻴﺔ) ( ) ( -6ﻨﺎﻗﺵ ﺒﻴﺎﻨﻴﺎ ﻋﺩﺩ ﻨﻘﻁ ﺘﻘﺎﻁﻊ ) (Cﻤﻊ ﺍﻟﻤﺴﺘﻘﻴﻡ ) ∆ ( ﺍﻟﺫﻱ ﻤﻌﺎﺩﻟﺘﻪ y = m :ﺤﻴﺙ mﻭﺴﻴﻁ ﺤﻘﻴﻘﻲ . ﺍﻟﺘﻤﺭﻴﻥ. 21 fﺩﺍﻟﺔ ﻤﻌﺭﻓﺔ ﺒﺎﻟﻤﻌﺎﺩﻟﺔ f ( x ) = −4 + 4 logx :
-1ﺍﺩﺭﺱ ﺘﻐﻴﺭﺍﺕ ﺍﻟﺩﺍﻟﺔ . f -2ﺍﺩﺭﺱ ﺍﻟﻔﺭﻭﻉ ﺍﻟﻼﻨﻬﺎﺌﻴﺔ ﻭﺍﻟﻤﺴﺘﻘﻴﻤﺎﺕ ﺍﻟﻤﻘﺎﺭﺒﺔ ﻟﻠﻤﻨﺤﻨﻰ Cﺍﻟﻤﻤﺜل) ( ;O → → ﻤﺘﺠﺎﻨﺱ ﻤﺘﻌﺎﻤﺩ ﻤﻌﻠﻡ ﻓﻲ f ﻟﺘﻐﻴﺭﺍﺕ i, j -3ﺃﻨﺸﺊ ) . (C ﺍﻟﺘﻤﺭﻴﻥ. 22 fﺜﻡ ﺃﻨﺸﺊ ﺘﻤﺜﻴﻠﻬﺎ ﺍﻟﺒﻴﺎﻨﻲ ﻓﻲ ﻤﻌﻠﻡ ﻤﺘﻌﺎﻤﺩ) ( x 1 ﺤﻴﺙ : f ﺍﺩﺭﺱ ﺘﻐﻴﺭﺍﺕ ﺍﻟﺩﺍﻟﺔ = logx . ;O → → ﻤﺘﺠﺎﻨﺱ i, j ﺍﻟﺘﻤﺭﻴﻥ. 23 fﺜﻡ ﺃﻨﺸﺊ ﺘﻤﺜﻴﻠﻬﺎ ﺍﻟﺒﻴﺎﻨﻲ ﻓﻲ ﻤﻌﻠﻡ ﻤﺘﻌﺎﻤﺩ) (x = log x − 1 : ﺤﻴﺙ f ﺍﺩﺭﺱ ﺘﻐﻴﺭﺍﺕ ﺍﻟﺩﺍﻟﺔ x . ﺒﻴﺎﻨﻴﺔ ﺒﺂﻟﺔ ;O → → ﻤﺘﺠﺎﻨﺱ i, j
ﺍﻟﺤـﻠــــــﻭل ﺍﻟﺘﻤﺭﻴﻥ. 1 -1ﺨﻁﺄ .ﺍﻟﺩﺍﻟﺔ ﻤﻌﺭﻓﺔ ﻤﻥ ﺃﺠل − x > 0ﻭ ﻋﻠﻴﻪ x < 0ﻭ ﻤﻨﻪ ﻓﻬﻲ ﻤﻌﺭﻓﺔ ﻋﻠﻰ []−∞;0 -2ﺼﺤﻴﺢ .ﺍﻟﺩﺍﻟﺔ ﻤﻌﺭﻓﺔ ﻤﻥ ﺃﺠل x > 0ﻭ ﻋﻠﻴﻪ x ≠ 0ﻭﺒﺎﻟﺘﺎﻟﻲ ﻓﻬﻲ ﻤﻌﺭﻓﺔ ﻋﻠﻰ ∗ -3ﺼﺤﻴﺢ .ﺍﻟﺩﺍﻟﺔ ﻤﻌﺭﻓﺔ ﻤﻥ ﺃﺠل x > 0 -4ﺨﻁﺄ .ﻷﻥ lnα 2 = 2 lnα :ﻟﻜﻥ ln 22 = α ln 2 -5ﺨﻁﺄ ln x > 0 .ﺘﻜﺎﻓﺊ x > 1ﺃﻱ [∞x ∈ ]−∞;−1[ ∪ ]1;+ -6ﺨﻁﺄ .ﺒل ln (a × b) = ln a + ln b -7ﺼﺤﻴﺢ .ﺇﺫﺍ ﻜﺎﻥ x < 1ﻓﺈﻥ ln x < ln1ﻭ ﻋﻠﻴﻪ ln x < 0 ( ∗ ﻤﺘﺯﺍﻴﺩﺓ ﺘﻤﺎﻤﺎ ﻋﻠﻰ ln ) ﻷﻥ ﺍﻟﺩﺍﻟﺔ +ﺨﻁﺄ .ﺍﻟﺩﺍﻟﺔ ﻤﻌﺭﻓﺔ ﻤﻥ ﺃﺠل x > 0ﻭ ln x ≠ 0ﻭ ﻋﻠﻴﻪ x > 0 -8ﻭ x ≠ 1ﻭ ﻤﻨﻪ ﻓﻬﻲ ﻤﻌﺭﻓﺔ ﻋﻠﻰ [∞]0;1[ ∪ ]1;+ -9ﺨﻁﺄ .ﺍﻟﻤﺴﺎﻭﺍﺓ ﺼﺤﻴﺤﺔ ﻤﻥ ﺃﺠل x > 0 -10ﺼﺤﻴﺢ . ln e2008 = 2008 ln e = 2008 .lim x = lim 1 ﻷﻥ = +∞ : ﺼﺤﻴﺢ -11 ln x ln x∞x→+ ∞x→+ x( )lim ln − x = lim ln z = ∞+ : ﻷﻥ ﺼﺤﻴﺢ -12∞x→− ∞z → + -13ﺼﺤﻴﺢ ﻷﻥ ( )ln −2 1830 = ln 21830 = 1830 ln 2 :ﻭﺒﺼﻔﺔ ﻋﺎﻤﺔ ﺇﺫﺍ ﻜﺎﻥ xﻋﺩﺩ ﺤﻘﻴﻘﻲ ﻏﻴﺭ ﻤﻌﺩﻭﻡ ﻭﻜﺎﻥ nﻋﺩﺩ ﻁﺒﻴﻌﻲ ﺯﻭﺠﻲ ﻓﺈﻥ ln xn = n ln x : -14ﺼﺤﻴﺢ .ﺇﺫﺍ ﻜﺎﻥ ln x2 = 2 ln x : x > 0ﻭ ﺇﺫﺍ ﻜﺎﻥ x < 0
ln x2 = 2 ln x : ﻭ ﻋﻠﻴﻪln x2 = ln ( − x )2 = 2 ln ( − x ) : ﻓﺈﻥ ln 12 = ln12 − ln 3 ﻷﻥ . ﺨﻁﺄ – 15 3 ln 12 = ln (4× 3) = ln 4 + ln 3 : ﻟﻜﻥ ln 3 ln 3 ln 3 . 2ﺍﻟﺘﻤﺭﻴﻥ : ﺍﻟﺘﺒﺴﻴﻁ1) ln e − ln e−3 = 1 − (−3) ln e = 1 ln e + 3×1 = 1 × 1 + 3 = 7 2 2 2 ln e 2( )2)lne3 e e3 1 1 ln e2 3 1 ln e 2 ln e − ln e2 = ln 2 − + = ln − 2 + ln e2 e2 = 3 − 1 + 2 = 3 2 2 1 3) 1 ln 25 + ln 2 = 5 ln 2 + ln 22 = ln 2 + 1 ln 2 = 9 ln 2 5 4 5 4 8 8 4) ln 2 2 − 3 ln 2 = ln 2× 1 − 3 ln 2 = ln 3 − 3 ln 2 2 2 2 22 22 = 3 × ln 2 − 3 × ln 2 = 0 2 2 ( ) ( )5)ln(128)2 − ln(16×32) = ln 27 2 − ln 24 ×25 = ln214 − ln29 = 14 ln 2 − 9 ln 2 = 5 ln 2 6) ln 243 + ln 610 + ln 1 = ln 35 + 10 ln 6 − ln (1024) 1024 = 5 ln 3 + 10 ln ( 2× 3) − ln 210 = 5 ln 3 + 10(ln 2 + ln 3) − 10 ln 2
= 5 ln 3 + 10 ln 2 + 10 ln 3 − 10 ln 2 = 15 ln 3 . 3ﺍﻟﺘﻤﺭﻴﻥ : ﺍﻟﻘﻴﻡ ﺍﻟﻤﻘﺭﺒﺔ• ln ( 2007)2006 = 2006 ln ( 2007) ln ( 2007)2006 15262, 02 : ﻭ ﻤﻨﻪ• ln (1962)1954 = 1954 ln (1962) ln (1962)1954 14841, 68 : ﻭ ﻤﻨﻪ• ln 1 0,13 1830• ln ( 2)1418 = 1418 ln 2 ( )ln 2 1418 982, 88 : ﻭ ﻤﻨﻪ• ln (2, 0005)12 = 12 ln ( 2, 0005) ln ( 2, 0005)12 8, 32 : ﻭ ﻤﻨﻪ( )• ln 25 × 37 × 53 = ln 25 + ln 37 + ln 53 = 5 ln 2 + 7 ln 3 + 3 ln 5 ( )ln 25 × 37 × 53 15, 98 : ﻭ ﻤﻨﻪ . 4ﺍﻟﺘﻤﺭﻴﻥ : ﺩﺭﺍﺴﺔ ﺍﻹﺸﺎﺭﺓ• a = 3 ln 7 − 5 ln 5 a = ln 73 − ln 55 = ln 73 = ln 343 55 3125 a < 0 : ﺇﺫﻥ ln 343 < 0 : ﻓﺈﻥ 343 <1 : ﺃﻥ ﺒﻤﺎ ﻭ 3125 3125
• b = 3 ln 2 − 1 ln 15 = ln 23 − ln (15) 1 2 2 b = ln 8 − ln 15 = ln 8 15 b > 0 : ﺇﺫﻥ 8 >0 : ﻭ ﻤﻨﻪ 8 >1 : ﻟﺩﻴﻨﺎ 15 15( )• c = ln 3 − 2 ( )c < 0 : ﻭﻋﻠﻴﻪln 3 − 2 < 0 : ﻭﻤﻨﻪ3 − 2 < 1 : ﻟﺩﻴﻨﺎ• d = ln 3 = ln 3 = ln 3 ln 0, 5 1 − ln 2 ln 2 d < 0 : ﺇﺫﻥ d = − ln 3 : ﻭﻋﻠﻴﻪ ln 2 . 5ﺍﻟﺘﻤﺭﻴﻥ : ﺍﻟﺘﺤﻘﻴﻕ ﻤﻥ ﺼﺤﺔ ﺍﻟﻤﺴﺎﻭﺍﺓ ( )2ln 2 3+ 4 3 −1 + ln 4 = 0 ( ) ( )2ln ln 2 3 + 4 2 2 3+4 3 −1 + 4 = ln 3 −1 + ln 4 ( ) ( )= ln 22 3 + 4 ln 3+2 3 −1 4 = 4−2 3 2 ( ) ( )= ln 2 − 3 2 + 3 = ln(4 − 3) = ln1 = 0 . 6ﺍﻟﺘﻤﺭﻴﻥ f ( x) = 1 x2 − x + ln x : ( ﻟﺩﻴﻨﺎ1 2 ] [: ﺤﻴﺙ0;+∞ ﻤﻌﺭﻓﺔ ﻭ ﻗﺎﺒﻠﺔ ﻟﻼﺸﺘﻘﺎﻕ ﻋﻠﻰf ﺍﻟﺩﺍﻟﺔ
f )′( x = x −1+ 1 = x2 − x+1 x x (2ﻟﺩﻴﻨﺎ f ( x ) = ln x2 − 4 :ﺤﻴﺙ { } ( )Df = x ∈ : x2 − 4 > 0 :x −∞ - 2 ∞2 +x2 − 4 + -+ ﺇﺫﻥ Df = ]−∞;−2[ ∪ ]2;+∞[ : f )′( x = 2x ﺍﻟﺩﺍﻟﺔ fﺘﻘﺒل ﺍﻻﺸﺘﻘﺎﻕ ﻋﻠﻰ D fﺤﻴﺙ : x2 − 4 (3ﻟﺩﻴﻨﺎ f ( x ) = x ln x :ﺤﻴﺙ Df = { x ∈ : x ≠ 0} : ﻭﻋﻠﻴﻪ Df = ]−∞ ; 0[ ∪ ]0 ; + ∞[ :f (′ )x = 1 ln x + ×x 1 D fﺤﻴﺙ : ﺘﻘﺒل ﺍﻻﺸﺘﻘﺎﻕ ﻋﻠﻰ f ﺍﻟﺩﺍﻟﺔ x ﺇﺫﻥ f ′ ( x) = ln x + 1 :∈Df ={x : xln x ≠ 0 , ﺤﻴﺙ x > 0} : f ( )x = x 1 x (4ﻟﺩﻴﻨﺎ : ln ﻭﻋﻠﻴﻪ Df = { x ∈ : x ≠ 0 , ln x ≠ 0 , x > 0} :ﻟﻜﻥ ln x ≠ 0 :ﺘﻜﺎﻓﺊ x ≠ 1 :ﻭ ﻋﻠﻴﻪ Df = ]0;1[ ∪ ]1;+∞[ : ﺍﻟﺩﺍﻟﺔ fﺘﻘﺒل ﺍﻻﺸﺘﻘﺎﻕ ﻋﻠﻰ D fﺤﻴﺙ : − 1. ln x + x 1 )− (ln x + 1 x ( x ln x)2f (′ )x = = ( x ln x)2 (5ﻟﺩﻴﻨﺎ f ( x ) = x ln ( − x ) :ﺤﻴﺙ Df = { x ∈ : − x > 0} : ﻟﻜﻥ − x > 0 :ﺘﻜﺎﻓﺊ x < 0 :ﻭﻤﻨﻪ Df = ]−∞;0[ : fﺘﻘﺒل ﺍﻻﺸﺘﻘﺎﻕ ﻋﻠﻰ D fﺤﻴﺙ : f (′ )x = 1 ln (− )x + x × −1 = ln (− )x + 1 −x
Df = x∈ : x−1 >0 , x −2 ≠ 0 : ﺤﻴﺙ f (x) = ln x−1 : ﻟﺩﻴﻨﺎ (6 x−2 x − 2 Df = ]−∞;1[ ∪ ]2;+∞[ : ﺇﺫﻥ x −∞ 1 2 ∞ +x−1 - + +x−2 - - +x−1 +- +x−2 : ﺤﻴﺙf ﺘﻘﺒل ﺍﻻﺸﺘﻘﺎﻕ ﻋﻠﻰD f ﺍﻟﺩﺍﻟﺔ 1.( x − 2) − 1.( x − 1) −1 f ′(x) = ( x − 2)2 = ( x − 2)2 x−1 x−1 x−2 x−2 f ′ ( x ) = ( −1 × x − 2 = ( x − −1 − 1) x − 1 x − 2) 2)( x{ } ( )Df = x∈ :e2x −5ex +6> 0 : ﺤﻴﺙf ( x) =ln e2x −5ex +6 : ( ﻟﺩﻴﻨﺎ7 τ 2 − 5τ + 6 : ﻨﺠﺩe x = τ : ﺒﻭﻀﻊe2x − 5e x + 6 : ﻨﺩﺭﺱ ﺇﺸﺎﺭﺓτ 2 −5τ + 6 = (τ − 2) (τ − 3) : ﻭﻋﻠﻴﻪτ2 = 3 , τ1 = 2 , ∆ = 1 : ﻭﻤﻨﻪ ( ) ( )e2x − 5e x + 6 = e x − 2 e x − 3 : ﻭﺒﺎﻟﺘﺎﻟﻲ x = ln 2 : ﻭﻤﻨﻪln e x = ln 2 : ﻭﻋﻠﻴﻪe x = 2 : ﺘﻜﺎﻓﺊe x − 2 = 0 x > ln 2 : ﻭﻤﻨﻪln e x > ln 2 : ﻭﻋﻠﻴﻪe x > 2 : ﺘﻜﺎﻓﺊe x − 2 > 0 x = ln 3 : ﻭﻤﻨﻪln e x = ln 3 : ﻭﻋﻠﻴﻪe x > 3 : ﺘﻜﺎﻓﺊe x − 3 > 0 x > ln 3 : ﻭﻤﻨﻪln e x > ln 3 : ﻭﻋﻠﻴﻪe x = 3 : ﺘﻜﺎﻓﺊe x − 3 = 0
x −∞ ln 2 ln 3 ∞ + ex − 2 e2 − 3 - + + - - + (ex − 2)(ex − 3) + - + Df = ]−∞;ln 2[ ∪ ]ln 3;+∞[ : ﻭﻤﻨﻪ ( )f ′x = 2e2x − 5e x : ﺤﻴﺙD f ﺘﻘﺒل ﺍﻻﺸﺘﻘﺎﻕ ﻋﻠﻰ f ﺍﻟﺩﺍﻟﺔ e2x − 5e x + 6 Df ={x∈ :x>0 } : ﺤﻴﺙ f ( x) = 1 ( ln x)2 : ( ﻟﺩﻴﻨﺎ8 2 Df = ]0;+∞[ : ﻭﻤﻨﻪ f ′( x) = 1 ×2× 1 × ( ln x) : ﺤﻴﺙ Df ﺘﻘﺒل ﺍﻻﺸﺘﻘﺎﻕ ﻋﻠﻰ f ﺍﻟﺩﺍﻟﺔ 2 x f ′( x) = ln x : ﺇﺫﻥ x . 7ﺍﻟﺘﻤﺭﻴﻥ : ﺤﺴﺎﺏ ﺍﻟﻨﻬﺎﻴﺎﺕ 1) lim x− lnx = lim x− 1 lnx = +∞ > x > x x→0 x→0 2) lim 1 = 0 > lnx x →0 x x 1 3) lim ln x2 + = lim ln 1 = lim ln = −∞ 1 x→+∞ 1 x→+∞ x→+∞ 1 + x2 x2 1 + x2
4) lim ln (ln x) = −∞ > x →1 5) lim e x = 0 > lnx x 0 →( )6) lim lnx x → +∞ x x2 − lnx = lim x x − = +∞ x → +∞7) lim lnx = lim lnz 2 = lim 2lnz =0 xx → +∞ z z z→+∞ z→+∞ z +∞ : ﻓﺈﻥx +∞ ( ﻟﻤﺎx2 = z ﺃﻱ x = z ) ﺒﻭﻀﻊ 18) lim lnx = lim ln 4 z = lim lnz 4 = lim 1 lnz =0 x4 z z 4 z x→+∞ z→+∞ z→+∞ z→+∞ x +∞ ( ﻟﻤﺎx = 4 z ﺃﻱx4 = z ) ﺒﻭﻀﻊ(( )) ( ( ) )9) lim ln x 2 2 2ln x 2lim (lnx)2 = x = lim : ﻓﺈﻥ z → +∞ 2xx → +∞ 2 x→+∞ x = lim 4 ln x 2 = lim 4 lnt 2 = 0 x t x → +∞ t → +∞ t +∞ : ﻓﺈﻥx +∞ : ( ﻟﻤﺎx = t ) ﺒﻭﻀﻊ 10) lim ( x − lnx) lnx = −∞ > x→0 11) lim x lnx = lim z lnz2 = lim 2z lnz = 0 > >> x→0 z→0 z→0 >> z 0 : ﻓﺈﻥx 0 ( ﻟﻤﺎx2 = z ﺃﻱx = z ) ﺒﻭﻀﻊ
1 ln 1 + 1 ln (1 + τ) = 1 x x = lim)12 lim x ln 1 + = lim τ 1 > ∞x → + ∞x→+ τ→0 x > ∞+ ( ﻟﻤﺎ 1 = τ ) ﺒﻭﻀﻊ x xﻓﺈﻥ τ 0 : ﺍﻟﺘﻤﺭﻴﻥ. 8 ﺤل ﺍﻟﻤﻌﺎﺩﻻﺕ : (1ﻟﺩﻴﻨﺎ lnx − ln ( x − 2) = 1 : ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑ D = { x ∈ : x > 0; x > 2} : ln x x 2 = ﻭﻋﻠﻴﻪ ﺍﻟﻤﻌﺎﺩﻟﺔ ﺘﻜﺎﻓﺊ lne : ﻭﻤﻨﻪ D = ]2;+∞[ : − ﺇﺫﻥ (1 − e) x = −e : x = xe − e ﻭﻤﻨﻪ : x x 2 = e ﺃﻱ ﺃﻥ : − ) ﻤﺭﻓﻭﺽ :ﻷﻥ ( x > 2 x = e e ﺃﻱ : x = −e ﻭﻤﻨﻪ : 1− 1−e ﻭﻋﻠﻴﻪ ﻟﻴﺱ ﻟﻠﻤﻌﺎﺩﻟﺔ ﺤﻠﻭل . (2ﻟﺩﻴﻨﺎ lnx2 = 4 : ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑ D = { x ∈ : x ≠ 0} :ﻭﻤﻨﻪ D = ∗ : ﻭﻋﻠﻴﻪ ﺍﻟﻤﻌﺎﺩﻟﺔ ﺘﻜﺎﻓﺊ lnx2 = 4 lne :ﺃﻱ lnx2 = lne4 : ﻭﻤﻨﻪ x2 = e4 :ﺃﻱ x = e2 :ﺃﻭ x = −e2 ﺇﺫﻥ ﺍﻟﺤﻠﻭل ﻫﻲ −e2 , e2 : (3ﻟﺩﻴﻨﺎ ( )ln ( x − 1) + ln ( x + 2) = ln x2 − 3x + 2 :ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑ { }D = x∈ : x −1 > 0, x + 2 > 0, x2 − 3x + 2 > 0 : ﻭﻤﻨﻪ x > 1 :ﻭ x > −2ﻭ x2 − 3x + 2 > 0ﻨﺤل ﺍﻟﻤﺘﺭﺍﺠﺤﺔ x2 = 2 , x1 = 1 , ∆ = 1 , x2 − 3x + 2 > 0 :
x −∞ 1 2 ∞+x2 − 3x + 2 > 0 + - +ﻭﻤﻨﻪ ﺍﻟﺤﻠﻭل ]−∞;1[ ∪ ]2;+∞[ :ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑ D = ]2;+∞[ :ﻭﻋﻠﻴﻪ ﺍﻟﻤﻌﺎﺩﻟﺔ ﺘﻜﺎﻓﺊ ( )ln ( x − 1) ( x + 2) = ln x2 − 3x + 2 : ﺇﺫﻥ ( x − 1) ( x + 2) = x2 − 3x + 2 :ﻭﻤﻨﻪ x2 + x − 2 = x2 − 3 x + 2 :ﺇﺫﻥ 4 x = 4 :ﻭﻋﻠﻴﻪ x = 1 : ﻭﻫﻭ ﻤﺭﻓﻭﺽ ﻭ ﻤﻨﻪ ﻟﻴﺱ ﻟﻠﻤﻌﺎﺩﻟﺔ ﺤﻠﻭل . (4ﻟﺩﻴﻨﺎ 2 ( lnx )2 + 5 lnx − 3 = 0 :ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑ D = { x ∈ : x > 0} :ﺤﻴﺙ D = ]0;+∞[ : ﺒﻭﻀﻊ lnx = t :ﻨﺠﺩ 2t 2 + 5t − 3 = 0 : t2 = 1 , t1 = −3 , ∆ = 49 ﻭﻤﻨﻪ : 2 ﻟﻤﺎ lnx = −3 : t = −3ﻭ ﻤﻨﻪ e Lnx = e−3 : lnx = 1 : t = 1 ﻟﻤﺎ τ = 1 ﺃﻱ : τ = e−3 ﻭﻋﻠﻴﻪ : 2 2 e3e, 1 ﺇﺫﻥ ﺍﻟﺤﻠﻭل ﻫﻲ : =x 1 e3 ﻭﻤﻨﻪ e Lnx = e 2 :ﺇﺫﻥ e : ﺍﻟﺘﻤﺭﻴﻥ. 9 ﺤل ﺍﻟﻤﺘﺭﺍﺠﺤﺎﺕ :∈D ={x ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑ : x > 0} : lnx < 1 (1ﻟﺩﻴﻨﺎ : 2 1 ﺤﻴﺙ D = 0; +∞ :ﻭ ﺍﻟﻤﺘﺭﺍﺠﺤﺔ ﺘﻜﺎﻓﺊ ] [lnx < lne 2 : 1 ﻭﻤﻨﻪ x < e 2 :ﺃﻱ x < e :ﻭﻋﻠﻴﻪ ﺤﻠﻭل ﺍﻟﻤﺘﺭﺍﺠﺤﺔ ﻫﻲ
ﺍﻟﻤﺠﻤﻭﻋﺔ . 0 ; e : (2ﻟﺩﻴﻨﺎ ln x < 1 :ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑ D = { x ∈ : x ≠ 0} :ﻭ ﺍﻟﻤﺘﺭﺍﺠﺤﺔ ﺘﻜﺎﻓﺊ ln x < lne :ﻭﻤﻨﻪ x < e :ﺇﺫﻥ −e < x < e : ﻭﻋﻠﻴﻪ ﺤﻠﻭل ﺍﻟﻤﺘﺭﺍﺠﺤﺔ ﻫﻲ ﺍﻟﻤﺠﻤﻭﻋﺔ ] [ ] [. −e;0 ∪ 0;e : (3ﻟﺩﻴﻨﺎ lnx + ln ( x − 1) > ln6 :ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑ : } D = { x ∈ : x > 0, x > 1ﺤﻴﺙ D = ]1;+∞[ :ﻭ ﺍﻟﻤﺘﺭﺍﺠﺤﺔ ﺘﻜﺎﻓﺊ lnx ( x − 1) < ln6 :ﺇﺫﻥ x2 − x > 6 :ﻭﻋﻠﻴﻪ x2 − x − 6 > 0 :ﻭﻤﻨﻪ x2 = 3 , x1 = −2 , ∆ = 25 :x −∞ -2 3 ∞+x2 − x − 6 + -+ ﻭﻋﻠﻴﻪ ﺤﻠﻭل ﺍﻟﻤﺘﺭﺍﺠﺤﺔ ﻫﻲ ﺍﻟﻤﺠﻤﻭﻋﺔ ]−∞;−2[ ∪ ]3;+∞[ :ﻟﻜﻥ [∞ D = ]1;+ﻭﻤﻨﻪ ﻤﺠﻤﻭﻋﺔ ﺤﻠﻭل ﺍﻟﻤﺘﺭﺍﺠﺤﺔ ﻫﻲ ]3;+∞[ : )ln ( x − 1 < 0 (4ﻟﺩﻴﻨﺎ : )ln ( x + 3ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑ { }D = x ∈ : x −1 > 0, x + 3 > 0, ln( x + 3) ≠ 0 : ﻭﻤﻨﻪ x + 3 ≠ 1 , x > −3 , x > 1 :ﻭﻋﻠﻴﻪ x ≠ −2 , x > −3 , x > 1 :ﺇﺫﻥ D = ]1;+∞[ : ﻨﺩﺭﺱ ﺇﺸﺎﺭﺓ ln ( x − 1) : ln ( x − 1) = 0ﺘﻜﺎﻓﺊ x − 1 = 1 :ﻭﻤﻨﻪ x = 2 : ln ( x − 1) > 0ﺘﻜﺎﻓﺊ x − 1 > 1 :ﻭﻤﻨﻪ x > 2 : ln ( x − 1) < 0ﺘﻜﺎﻓﺊ x < 2 : ﻨﺩﺭﺱ ﺇﺸﺎﺭﺓ Ln ( x + 3) : ln ( x + 3) = 0ﺘﻜﺎﻓﺊ x + 3 = 1 :ﻭﻤﻨﻪ x = −2 : ln ( x + 3) > 0ﺘﻜﺎﻓﺊ x + 3 > 1 :ﻭﻤﻨﻪ x > −2 :
x 1 x < −2 : ﺘﻜﺎﻓﺊln ( x + 3) < 0 ln ( x − 1) 2 +∞ ln ( x + 3) -+ ++ln ln ( x − 1) ln ( x + 3) -+ ] [. 1;2 : ﻤﺠﻤﻭﻋﺔ ﺍﻟﺤﻠﻭلD = ]0;+∞[ : ( ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑlnx )2 − 8 lnx + 7 > 0 : ( ﻟﺩﻴﻨﺎ5 τ 2 − 8τ + 7 > 0 : ﻨﺠﺩlnx = τ ﺒﻭﻀﻊ τ 2 = 7 , τ1 = 1 , ∆ = 36 : ﻭﻤﻨﻪ τ 2 − 8τ + 7 = (τ − 1) (τ − 7) : ﺇﺫﻥ ( lnx)2 − 8 lnx + 7 = ( lnx − 1) ( lnx − 7) : ﻭﻋﻠﻴﻪ x = e : ﻭﻤﻨﻪlnx = 1 ﺘﻜﺎﻓﺊlnx − 1 = 0x > e ﺇﺫﻥlnx > lne : ﻭﻤﻨﻪlnx > 1 ﺘﻜﺎﻓﺊlnx − 1 > 0x = e7 ﺇﺫﻥlnx = lne7 : ﻭﻤﻨﻪlnx = 7 ﺘﻜﺎﻓﺊlnx − 7 = 0x > e7 ﺇﺫﻥlnx > lne7 : ﻭﻤﻨﻪlnx > 7 ﺘﻜﺎﻓﺊlnx − 7 > 0 x 0 e e7 +∞ lnx − 1 -++ lnx − 7 --+( lnx − 1) ( lnx − 7) + - + ] [0 ; e ∪ e7 ; + ∞ : ﺇﺫﻥ ﻤﺠﻤﻭﻋﺔ ﺤﻠﻭل ﺍﻟﻤﺘﺭﺍﺠﺤﺔ ﻫﻲ
(6ﻟﺩﻴﻨﺎ x2 − 4x lnx ≥ 0 :ﻤﺠﻤﻭﻋﺔ ﺍﻟﺘﻌﺭﻴﻑ ( )] [D = 0;+∞ : x 0 1 ∞4 + x2 − 4x - - + - + + lnx + - +( x2 − 4x) lnx ﻤﺠﻤﻭﻋﺔ ﺤﻠﻭل ﺍﻟﻤﺘﺭﺍﺠﺤﺔ . ]0 ; 1] ∪ [4 ; + ∞[ : ﺍﻟﺘﻤﺭﻴﻥ. 10 ﺘﻌﻴﻥ ﺍﻟﺩﻭﺍل ﺍﻷﺼﻠﻴﺔ : g∈ g ( x) = x3 − 2 lnx + c ; c ﺤﻴﺙ : f ( )x = 3x2 − 2 (1ﻟﺩﻴﻨﺎ : x ﺤﻴﺙ : f ( )x = − x3 + 1 + ( x 1 (2ﻟﺩﻴﻨﺎ : x−1 − 1)2)g( x = x4 + ln( x − 1) - x 1 1 + c ∈; c 4 − f ( )x = 1 2x − 2 ﺤﻴﺙ : f )(x = x−1 (3ﻟﺩﻴﻨﺎ : 2 x2 − 2x x2 − 2x = )g(x 1 (ln x2 − 2x) + c ; ∈c ﻭﻤﻨﻪ : 2f ( )x = 1 (× lnx )2 ﺤﻴﺙ : f ( )x = ( lnx )2 (4ﻟﺩﻴﻨﺎ : x x (g )x = ( lnx )3 + c , ∈c ﻭﻤﻨﻪ : 3∈ g ( x) = ln (sin x) + c , c ﺤﻴﺙ : f ( )x = cosx (5ﻟﺩﻴﻨﺎ : sin x
( )g ( x) = ln ex + 1 + c , c ∈ : ﺤﻴﺙ f ( x) = ex 1 : ( ﻟﺩﻴﻨﺎ6 ex + . 11ﺍﻟﺘﻤﺭﻴﻥ : ﻨﺒﻴﻥ ﺃﻥ-1 f ( x) = ax + b + x c 3 + d + x+1f ( x) = ( ax + b)( x + 3)( x + 1) + c ( x + 1) + d ( x + 3) ( x + 3)( x + 1) ( )f ( x) = (ax + b) x2 + 4x + 3 + cx + c + dx + d x2 + 4x + 3 f ( x) = ax 3 + 4ax 2 + 3ax + bx2 + 4bx + 3b + cx + c + dx + d x2 + 4x + 3 f ( x ) = ax 3 + ( 4a + b) x2 + ( 3a + 4b + c ) x + 3b + c + d x2 + 4x + 3 a = −1 : ﻭ ﻋﻠﻴﻪ a = −1 : ﻭﻤﻨﻪ b = −8 + e 4a + b = −12 + e c = 26 3a + 4b + c = −9 + 4e d = −4 3b + c + d = 3e − 2 f ( x) = − x − 8 + e + 26 − x 4 1 : ﺇﺫﻥ x+3 + : g ﺘﻌﻴﻥ ﺍﻟﺩﺍﻟﺔ ﺍﻷﺼﻠﻴﺔ-2 g ( x ) = − 1 x2 − 8 x + ex + 26 ln ( x + 3) − 4 ln ( n + 1) + c 2 g ( x ) = − 1 x2 + ( −8 + e ) x + 26 ln ( x + 3) − 4 ln ( x + 1) + c , c∈ 2 g (0) = 1 : ﺤﻴﺙh( x ) = g ( x ) : h ﺘﻌﻴﻴﻥ-3 c = −26 ln3 : ﻭﻋﻠﻴﻪ26 ln3 + c = 0 : ﻭﻤﻨﻪg (0) = 1 : ﻟﺩﻴﻨﺎ
h( x) = - 1 x2 + ( -8 + e) x + 26 ln( x + 3) -4 ln( x + 1) -26 ln3 : ﺇﺫﻥ 2 . 12ﺍﻟﺘﻤﺭﻴﻥ : f ﺩﺭﺍﺴﺔ ﺘﻐﻴﺭﺍﺕ-1 Df = ]−1;+∞[ : ﺤﻴﺙDf = { x ∈ : x + 1 > 0} : ﻟﺩﻴﻨﺎ lim f ( x) = lim ( − x2 + x + 2 ln ( x + 1)) = −∞> > x →−1 x →−1 lim f ( x) = lim − x2 + x + 2 ln ( x + 1) x→+∞ x → +∞ = lim ( x + 1 ) − x 2+ x + 2 ln ( x + 1) x +1 x→ +∞ x+1 x2 −1 + 1 x = lim + 2 ln ( x + 1 ) x→ +∞ x 1 + 1 x+1 x x −1 + 1 x = lim 1 + 2 ln ( x + 1) = −∞ x x → +∞ 1+ x+1 • f ′( x) = −2 x +1+ 2 x+1 f ′ ( x ) = ( −2 x + 1) (x+ 1) + 2 x +1 f ′( x) = −2 x 2 − 2x + x + 1+ 2 x+1 f ′( x) = −2 x 2 − x + 3 x + 1
) f ′ ( xﻟﻪ ﻨﻔﺱ ﺇﺸﺎﺭﺓ ﺍﻟﺒﺴﻁ . ∆ = 25 : ﻨﺩﺭﺱ ﺇﺸﺎﺭﺓ − 2x2 − x + 3 , x1 = 1 x2 = − 3 2x -1 1 ∞+−2x2 − x + 3 + - ﺇﺫﻥ fﻤﺘﻨﺎﻗﺼﺔ ﺘﻤﺎﻤﺎ ﻋﻠﻰ ∞ 1;+ﻭ ﻤﺘﺯﺍﻴﺩﺓ ﺘﻤﺎﻤﺎ ﻋﻠﻰ ] ] [ [−1 ; 1 x -1 1 ∞+ +)f ′(x 2.ln2 - ∞−)f (x ∞− f (1) = 2 ln2 -ﺩﺭﺍﺴﺔ ﺍﻟﻔﺭﻭﻉ ﺍﻟﻼﻨﻬﺎﺌﻴﺔ :ﻫﻨﺎﻟﻙ ﻓﺭﻋﻴﻥ ﻻﻨﻬﺎﺌﻴﻴﻥ ﺒﻤﺎ ﺃﻥ lim f ( x ) = −∞ :ﻓﺈﻥ x = −1 :ﻤﻌﺎﺩﻟﺔ ﻤﺴﺘﻘﻴﻡ ﻤﻘﺎﺭﺏ > x →−1 lim f )(x = lim − x + 1 + 2 ln ( x+ )1 ﻭ ﻟﺩﻴﻨﺎ : x ∞x→+ x ∞x→+ = lim x + 1+ (2 x+ )1 ln ( x + 1) = ∞− − x ∞x → + x+1
ﺇﺫﻥ ﻴﻭﺠﺩ ﻓﺭﻉ ﻗﻁﻊ ﻤﻜﺎﻓﺊ ﺒﺎﺘﺠﺎﻩ ﻤﺤﻭﺭ ﺍﻟﺘﺭﺍﺘﻴﺏ ﻋﻨﺩ ∞. + -2ﺇﻴﺠﺎﺩ ﺍﻟﻤﻤﺎﺴﺎﺕ ﺫﺍﺕ ﻤﻌﺎﻤل ﺍﻟﺘﻭﺠﻴﻪ : 3 −2x2 − x + 3 = 3 : ﻋﻠﻴﻪ ﻭ ﻨﺤل ﺍﻟﻤﻌﺎﺩﻟﺔ f ′ ( x ) = 3 x+1 ﺇﺫﻥ −2x2 − x + 3 = 3x + 3 :ﻭ ﻋﻠﻴﻪ −2x2 − 4 x = 0 : ﻭ ﻋﻠﻴﻪ −2x ( x + 2) = 0 :ﻭ ﻤﻨﻪ x = 0 :ﺃﻭ x = −2 ﺇﺫﻥ -2 ) x = 0 :ﻗﻴﻤﺔ ﻤﺭﻓﻭﻀﺔ (ﺇﺫﻥ ﻫﻨﺎﻙ ﻤﻤﺎﺱ ﻭﺍﺤﺩ ﻋﻨﺩ ﺍﻟﻨﻘﻁﺔ ﺫﺍﺕ ﺍﻟﻔﺎﺼﻠﺔ 0ﻭﻤﻌﺎﺩﻟﺘﻪ )y = f ′ (0) × ( x − 0) + f (0 ﺤﻴﺙ f (0) = 0ﻭ ﻋﻠﻴﻪ y = 3x : -3ﻨﺒﻴﻥ ﺃﻥ f ( x ) = 0ﺘﻘﺒل ﺤﻼ :f 5 = − 25 + 5 + 2 ln 7 = −15 + 2 ln 7 2 4 2 2 4 2 f 5 −1, 24 2 )f (2) = −2 + 2 ln3 ; f (2 0,19 ; 2 5 f ﻭﻋﻠﻴﻪ ﺍﻟﺩﺍﻟﺔ ﻤﺴﺘﻤﺭﺓ ﻭ ﻤﺘﻨﺎﻗﺼﺔ ﺘﻤﺎﻤﺎ ﻋﻠﻰ ﺍﻟﻤﺠﺎل 2 ﺇﺫﻥ ﺤﺴﺏ ﻤﺒﺭﻫﻨﺔ ﺍﻟﻘﻴﻡ ﺍﻟﻤﺘﻭﺴﻁﺔ f (2). f 5 < 0 : ﻟﺩﻴﻨﺎ ﻭ 2 ( )2< x0 < 5 ; f x0 =0 x0ﺒﺤﻴﺙ : ﻴﻭﺠﺩ ﻋﺩﺩ ﻭﺤﻴﺩ 2 -4ﺇﻨﺸﺎﺀ ﺍﻟﻤﻤﺴﺎﺕ ﻭ ) : (C
y 3 2 1 -3 -2 -1 0 1 2 3x -1 )(C -2 ) (γ) (γ -3 -4 -5ﺃ( ﺇﺜﺒﺎﺕ ﺃﻥ gﺯﻭﺠﻴﺔ :ﻟﺩﻴﻨﺎ Dg = :ﻭ ﻋﻠﻴﻪ ﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩ xﻤﻥ − x ∈ Dg : Dgﻭ ) g ( − x ) = g ( xﻭ ﻤﻨﻪ gﺯﻭﺠﻴﺔ . ﺏ( ﻜﺘﺎﺒﺔ g xﺩﻭﻥ ﺭﻤﺯ ﺍﻟﻘﻴﻤﺔ ﺍﻟﻤﻁﻠﻘﺔ ( ): g ( x) = − x2 + x + 2 ln ( x + 1) ; x > 0 g ( x ) = − x2 − x + 2 ln ( − x + )1 ; x>0 ﺝ( ﺇﻨﺸﺎﺀ ) : γﻓﻲ ﺍﻟﺭﺴﻡ ﺍﻟﺴﺎﺒﻕ () ( -ﻤﻥ ﺃﺠل g ( x ) = f ( x ) : x > 0ﻭ ﻤﻨﻪ ) (γﻴﻨﻁﺒﻕ ﻋﻠﻰ )(c -ﻤﻥ ﺃﺠل : x < 0ﺍﻟﺩﺍﻟﺔ gﺯﻭﺠﻴﺔ ﻭ ﻋﻠﻴﻪ ﺒﻴﺎﻨﻬﺎ ﻤﺘﻨﺎﻅﺭ ﺒﺎﻟﻨﺴﺒﺔ ﻟﻤﺤﻭﺭ ﺍﻟﺘﺭﺍﺘﻴﺏ . ﺍﻟﺘﻤﺭﻴﻥ. 13 -1 – Iﺍﻟﺤﺴﺎﺏ ϕ (1) = 0 ; ϕ ( 3) = 0 : -2ﺩﺭﺍﺴﺔ ﺍﻟﺘﻐﻴﺭﺍﺕ :
Dϕ = { x ∈ : x − 2 ≠ 0} Dϕ = ]−∞;2[ ∪ ]2;+∞[ lim x2 − 4x + 3 + 6 ln x − 2 = +∞ x→−∞ lim ϕ ( x) = lim x2 − 4x + 3 + 6 ln x − 2 = +∞ x→−∞ x→−∞ lim ϕ ( x) = lim x2 − 4x + 3 + 6 ln x − 2 = −∞ >> x→2 x→2 lim ϕ ( x) = lim x2 − 4x + 3 + 6 ln x − 2 = −∞ << x→−∞ x→2 lim ϕ ( x) = lim x2 − 4x + 3 + 6ln x − 2 = +∞ x→+∞ x→+∞ ϕ′( x) = 2x − 4+ 6 2 x− ϕ′( x) = (2x − x)( x − 2) + 6 = 2( x − 2)2 + 6 x−2 x−2 : ﻭ ﻋﻠﻴﻪ2 ( x − 2)2 + 6 > 0 : ﻷﻥx − 2 ﻟﻪ ﻨﻔﺱ ﺇﺸﺎﺭﺓϕ ′ ( x ) x −∞ 2 +∞ϕ′( x) -+ x ]−∞;2[ ] ﻭ ﻤﺘﻨﺎﻗﺼﺔ ﺘﻤﺎﻤﺎ ﻋﻠﻰ2;+∞[ ﻤﺘﺯﺍﻴﺩﺓ ﺘﻤﺎﻤﺎ ﻋﻠﻰϕϕ′( x) −∞ 2 3 +∞ϕ ( x) -+ +∞ +∞ −∞ −∞ : ϕ ( x ) ﺍﺴﺘﻨﺘﺎﺝ ﺇﺸﺎﺭﺓ-3 : ﻤﻥ ﺠﺩﻭل ﺘﻐﻴﺭﺍﺕ ﺍﻟﺩﺍﻟﺔ ﻓﺈﻥ ﺇﺸﺎﺭﺓ ﺘﻜﻭﻥ ﻜﻤﺎ ﻴﻠﻲ
x −∞ 1 2 3 +∞ϕ(x) + -- + f ′ ( x) = ( ϕ (x) : ( ﻨﺒﻴﻥ ﺃﻥ1 (II x − 2)2 Df = − {2} : ﺤﻴﺙDf = { x ∈ : x − 2 ≠ 0} : ﻟﺩﻴﻨﺎ 5 1 2 × ( x − 2) − ln x − 2 x− ( x − 2)2f ′( x) = 1+ − 2)2 − 6× ( x f ′( x) = (x − 2)2 + 5 − 6 + 6ln x − 2 ( x − 2)2 f ′(x) = x2 − 4x + 4 − 1 + 6ln x−2 ( x − 2)2 f ′ ( x) = ( ϕ (x) : ﻭ ﻋﻠﻴﻪ x − 2)2 : f ( ﺍﺴﺘﻨﺘﺎﺝ ﺘﻐﻴﺭﺍﺕ2 lim f ( x) = lim x + 2 − x 5 2 + 6 ln (− x + 2) = −∞ − x→−∞ x → −∞ −x + 2 lim f ( x) = lim x + 2 − 5 − 6ln x − 2 = +∞ < < − x − 2 x→2 x 2 x→2 ( )= 1 lim x − 2 ( x + 2) ( x − 2) − 5 − 6ln x − 2 = −∞ < x→2 lim f ( x) = lim x + 2− 5 − 6ln x − 2 > > − x − 2 x 2 x→2 x→2 = lim 1 2 ( x + 2)( x − 2) − 5− 6ln x − 2 = +∞ > x− x→2
lim f = )(x lim x + 2 − 5 − 6ln x − 2 ∞= + − x − 2∞x→+ ∞x→+ x 2 f ′ ( )x = ( ϕ )( x x − 2)2 ﻭ ﻤﻨﻪ ) f ′ ( xﻟﻪ ﻨﻔﺱ ﺇﺸﺎﺭﺓ ) ϕ ( xﻭ ﻋﻠﻴﻪ : x −∞ 1 2 ∞3 +)f ′( x +--+ ﺇﺫﻥ fﻤﺘﺯﺍﻴﺩﺓ ﺘﻤﺎﻤﺎ ﻋﻠﻰ ﻜل ﻤﻥ ﺍﻟﻤﺠﺎﻟﻴﻥ −∞ ; 1ﻭ ∞ [ [ ] ]3 ; + ﻭ ﻤﺘﻨﺎﻗﺼﺔ ﺘﻤﺎﻤﺎ ﻋﻠﻰ ﻜل ﻤﻥ ﺍﻟﻤﺠﺎﻟﻴﻥ 1 ; 2ﻭ ] ] [ [2 ; 3
x −∞ 1 ∞2 3 + -+ )f ′( x +- 8 ∞−∞ + )f (x ∞+∞ − 0 ﺇﺫﻥ f (1) = 8 , f ( 3) = 0 : (3ﺩﺭﺍﺴﺔ ﺍﻟﻔﺭﻭﻉ ﻻﻨﻬﺎﺌﻴﺔ : ﻫﻨﺎﻟﻙ 4ﻓﺭﻭﻉ ﺍﻟﻼﻨﻬﺎﺌﻴﺔ ﻭ ﻤﺴﺘﻘﻴﻡ ﺍﻟﻤﻘﺎﺭﺏ ﻤﻌﺎﺩﻟﺘﻪ x = 2 lim f ( )x − ( x + 2) = 0 ∞x →+ ﻭ ﻋﻠﻴﻪ y = x + 2ﻤﻌﺎﺩﻟﺔ ﺍﻟﻤﺴﺘﻘﻴﻡ ﺍﻟﻤﻘﺎﺭﺏ ﺍﻟﻤﺎﺌل ﻋﻨﺩ ∞ +ﻭ ﻋﻨﺩ ∞− (4ﺍﻟﺤﺴﺎﺏ : f )( −1 = 1 + 5 4, 8 3 f )(0 = 2 + 5 + 3ln2 6, 5 2 f ( )4 = 6 − 5 − 3ln2 1, 4 2 f )( −4 = −2 + 5 + ln6 0, 6 6 (5ﺍﻟﺘﺤﻘﻕ ﻤﻥ ﺃﻥ wﻤﺭﻜﺯ ﺘﻨﺎﻅﺭ : ﻨﺘﺤﻘﻕ ﻤﻥ ﺃﻨﻪ ﻤﻥ ﺃﺠل ﻜل ﻋﺩﺩ ﺤﻘﻴﻘﻲ xﻤﻥ 4 − x ∈ D f : D fﻭ ﻫﻭ ﻤﺤﻘﻕ ﻭ ﻜﺫﻟﻙ . f (4− x)+ f (x) = 8f (4− )x + f ( )x = 6− x− 5 − 6ln 2− x + x+ 2− 5− − 6ln 2− x 2− 2− x x−2 x−2 x
= 8+ x 5 2 + 6 ln x − 2 − 5 6ln x − 2 =8 − x−2 x−2− x−2 ﺇﺫﻥ ) w ( 2;4ﻤﺭﻜﺯ ﺘﻨﺎﻅﺭ ﻟﻠﻤﻨﺤﻨﻰ ). (Γ -6ﺇﻨﺸﺎﺀ ): (Γ y 8 7 6 5 4 3 2 1-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7x -1 -2 -3 ﺍﻟﺘﻤﺭﻴﻥ. 14 -1ﺩﺭﺍﺴﺔ ﺍﻻﺴﺘﻤﺭﺍﺭﻴﺔ ﻋﻨﺩ 0ﻤﻥ ﺍﻟﻴﻤﻴﻥ [ [D f = 0;+∞ :lim f ( )x = lim− xln1+ 1 = lim− ln 1 + 1 = lim − ln(1+ )t = 0 > > x > 1 x ∞t →+ tx→0 x→0 x→0 x ﺇﺫﻥ fﻤﺴﺘﻤﺭﺓ ﻋﻨﺩ 0ﻤﻥ ﺍﻟﻴﻤﻴﻥ .
-2ﺩﺭﺍﺴﺔ ﻗﺎﺒﻠﻴﺔ ﺍﻻﺸﺘﻘﺎﻕ ﻋﻨﺩ 0ﻤﻥ ﺍﻟﻴﻤﻴﻥ : − xln 1 + 1 lim f (x)− f )(0 = lim x = lim− ln 1 + 1 = ∞− > > x x−0 > xx→0 x→0 x→0 ﺇﺫﻥ fﻻ ﺘﻘﺒل ﺍﻻﺸﺘﻘﺎﻕ ﻋﻨﺩ 0ﻤﻥ ﺍﻟﻴﻤﻴﻥ ﻭ ﺍﻟﺒﻴﺎﻥ Cﻴﻘﺒل ﻨﺼﻑ) ( ﻤﻤﺎﺱ ﻴﻭﺍﺯﻱ ﻤﺤﻭﺭ ﺍﻟﺘﺭﺍﺘﻴﺏ ﻋﻨﺩ ﺍﻟﻨﻘﻁﺔ ﺫﺍﺕ ﺍﻟﻔﺎﺼﻠﺔ . 0 -3ﺤﺴﺎﺏ ) f ′ ( xﻭ ) : f ′′ ( x −1 f (′ )x = ( )−1 × ln 1 + 1 + (− ×)x x2 1 x x 1 + 1 f (′ )x = −ln 1 + 1 + x 1 x + x 1 f (′ )x = −ln 1 + 1 + x 1 1 x + −1f ( ′′ )x = − x2 1 − 1 x 1+ ( x + 1)2f )′′ ( x = − (x 1 − (x 1 = +x+1− x )x + 1 + 1)2 x ( x + 1)2
f ′′ ( x) = − x ( 1 1)2 x+ lim f ′( x) = lim − ln 1 + 1 + 1 = 0 x x+1 x→+∞ x→+∞ : f ′ ( x ) ﺍﺴﺘﻨﺘﺎﺝ ﺇﺸﺎﺭﺓ- x 0 +∞ f ′′ ( x) + 0 f ′(x) −∞ f ′ ( x ) < 0 ﻨﻼﺤﻅ ﺃﻥ : f ﺩﺭﺍﺴﺔ ﺘﻐﻴﺭﺍﺕ-4lim f ( x) = lim − xln1+ 1 = lim − ln1+ 1 = lim− ln(1+ t) = −1 x 1 x x→+∞ x→+∞ x→+∞ t→0 t x .( t= 1 ) ﺒﻭﻀﻊ x [ [0;+∞ ﻤﺘﻨﺎﻗﺼﺔ ﺘﻤﺎﻤﺎ ﻋﻠﻰf ﻭ ﻤﻨﻪf ′ ( x ) < 0 ﻭ ﻟﺩﻴﻨﺎ x 0 +∞ f ′( x) - 0 −1 f ′′ ( x)
(5ﺇﻨﺸﺎﺀ ) y = −1 : (Cﻤﻌﺎﺩﻟﺔ ﻤﺴﺘﻘﻴﻡ ﻤﻘﺎﺭﺏ y0,5 0 0,5 1 1,5 2 2,5 3 3,5 4 x-0,5 )(C -1 (6ﺤﺴﺎﺏ ) : g′ ( x g′ ( x) = 1. f ( x) − 1 g′( x) = f ( x) −1 (g′ )x = − xLn 1 + 1 − 1 x -ﺍﺴﺘﻨﺘﺎﺝ ﺩﺍﻟﺔ ﺃﺼﻠﻴﺔ ﻟﻠﺩﺍﻟﺔ : f ﻤﻤﺎ ﺴﺒﻕ g′ ( x) = f ( x) − 1ﻭﻤﻨﻪ f ( x) = g′ ( x) + 1 : ﻭﻋﻠﻴﻪ ﺍﻟﺩﻭﺍل hﺤﻴﺙ h( x ) = g ( x ) + x + c ; c ∈ : ﻫﻲ ﺩﻭﺍل ﺃﺼﻠﻴﺔ ﻟﻠﺩﺍﻟﺔ fﻋﻠﻰ ∞] [. 0;+ ﺍﻟﺘﻤﺭﻴﻥ. 15 -1ﺩﺭﺍﺴﺔ ﺘﻐﻴﺭﺍﺕ : f }Df = { x ∈ : 6 − x < 0 ﺇﺫﻥ Df = ]−∞;6[ :lim f )(x = lim 2x − 11 − ln (6 − )x = ∞− x−6∞x→− ∞x→−
lim f ( )x = lim 2x − 11 − ln (6 − )x < < x−6x→6 x→6= lim x 1 6 2 x − 11 + (6 − x )ln (6 − x ) = ∞− < − x→6 f )′(x = (2 x − 6) − 1(2x − )11 − −1 ( x − 6)2 6− x = )f ′(x −1 − 1 6 = )−1 − ( x − 6 x− ( x − 6)2 ( x − 6)2 f ′ ( x ) = −x + 5 ( x − 6)2 f ′ ( x ) = 0ﺘﻜﺎﻓﺊ − x + 5 = 0 :ﻭﻤﻨﻪ x = 5 : f ′ ( x ) > 0ﺘﻜﺎﻓﺊ − x + 5 > 0 :ﻭﻤﻨﻪ x < 5 : ﺇﺫﻥ fﻤﺘﺯﺍﻴﺩﺓ ﺘﻤﺎﻤﺎ ﻋﻠﻰ ] ]−∞;5 f ′ ( x ) < 0ﺘﻜﺎﻓﺊ x > 5 :ﻭ ﻤﻨﻪ fﻤﺘﻨﺎﻗﺼﺔ ﺘﻤﺎﻤﺎ ﻋﻠﻰ [ [5;6 x ∞− 56)f ′( x - - 1)f (x ∞− ∞− f ( )5 = −1 = 1 ﺇﺫﻥ : −1 -2ﻤﻌﺎﺩﻟﺔ ﺍﻟﻤﻤﺎﺱ :
f )′(0 = 5 ; f ( )0 = 11 − Ln6 36 6 )y = f ′(0)( x − 0) + f (0 y = 5 x + 11 − ln6 36 6 -3ﺍﻟﺤﺴﺎﺏ : f ( )−1 = 13 − ln6 −0,16 8 f )(0 = 11 − ln6 0, 04 6 f )(3 = 5 − ln3 0, 56 3 f )(4 = 3 − ln2 0, 80 2 -4ﻓﻲ ﺍﻟﻤﺠﺎل −1 ; 0ﺍﻟﺩﺍﻟﺔ fﻤﺴﺘﻤﺭﺓ ﻭ ﻤﺘﺯﺍﻴﺩﺓ ﺘﻤﺎﻤﺎ ﻭ ﻟﺩﻴﻨﺎ [ ]: f ( −1) . f (0) < 0ﻭ ﻤﻨﻪ ﻴﻭﺠﺩ ﻋﺩﺩ ﻭﺤﻴﺩ αﺒﺤﻴﺙ f (α ) = 0 -5ﻟﺩﻴﻨﺎf (5) = 1 − ln1 = 1 : ﻓﻲ ﺍﻟﻤﺠﺎل 5;6ﺍﻟﺩﺍﻟﺔ fﻤﺴﺘﻤﺭﺓ ﻭ ﻤﺘﻨﺎﻗﺼﺔ ﺘﻤﺎﻤﺎ[ [ ﻭﻟﺩﻴﻨﺎ f (5) > 0 :ﻭ ∞ lim f ( x ) = −ﻭﻋﻠﻴﻪ ﻴﻭﺠﺩ ﻋﺩﺩ < x→6 ﻭﺤﻴﺩ βﺒﺤﻴﺙ f ( β ) = 0 : -6ﺇﻨﺸﺎﺀ ) : (Clim f )(x = lim 2x − 11 ln (6 − )x =0 x2 − 6x∞x→− x ∞x → − −x ﻭ ﻤﻨﻪ Cﻴﻘﺒل ﻓﺭﻉ ﻗﻁﻊ ﻤﻜﺎﻓﺊ ﺒﺎﺘﺠﺎﻩ ﻤﺤﻭﺭ ﺍﻟﻔﻭﺍﺼل ﻋﻨﺩ ∞( )−
x = 6ﻤﻌﺎﺩﻟﺔ ﻤﺴﺘﻘﻴﻡ ﻤﻘﺎﺭﺏ y 1-5 -4 -3 -2 -1 0 1 2 3 4 5 6x -1 -2 -3 -7ﺍﻟﻤﻨﺎﻗﺸﺔ ﺍﻟﺒﻴﺎﻨﻴﺔ :. ﺍﻹﺸﺎﺭﺓ ﻓﻲ ﻤﺨﺘﻠﻔﻴﻥ ﺤﻠﻴﻥ ﻟﻠﻤﻌﺎﺩﻟﺔ : m ∈ ;∞− 11 − Ln6 ﻟﻤﺎ • 6 . ﻤﻌﺩﻭﻡ ﺃﺨﺭ ﻭ ﻤﻭﺠﺏ ﺤل ﻟﻠﻤﻌﺎﺩﻟﺔ : m = 11 − Ln6 ﻟﻤﺎ • 6 . ﻤﻭﺠﺒﻴﻥ ﺤﻠﻴﻥ ﻟﻠﻤﻌﺎﺩﻟﺔ : m ∈ 11 − Ln6 ; 1 ﻟﻤﺎ • 6 • ﻟﻤﺎ : m = 1ﻟﻠﻤﻌﺎﺩﻟﺔ ﺤل ﻤﻀﺎﻋﻑ ﻤﻭﺠﺏ . • ﻟﻤﺎ [∞ : m ∈ ]1;+ﻻ ﺘﻭﺠﺩ ﺤﻠﻭل . -8ﺍﻟﻤﻨﺎﻗﺸﺔ ﺍﻟﺒﻴﺎﻨﻴﺔ ﻟﻠﻤﺘﺭﺍﺠﺤﺔ ( )f x ≤ 0 : f ( x) ≤ 0ﺘﻜﺎﻓﺊ x ∈ ]−∞; β ] ∪ [α;6[ : -9ﺘﻌﻴﻴﻥ aﻭ : b 2x − 11 = a + b 6 x−6 x− 2x − 11 = ax − 6x + b x − 6 x −6
a = 2 a = 2 ﻭ ﻤﻨﻪ : ﻭ ﻤﻨﻪ b = 1 : −6a + b = −11 2x − 11 = 2+ 1 ﺇﺫﻥ : x −6 x−6 -10ﺘﻌﻴﻴﻥ ﺍﻟﺩﺍﻟﺔ ﺍﻟﻤﺸﺘﻘﺔ ﻟﻠﺩﺍﻟﺔ ] [Dg = −∞;6 : g g′ ( x ) = 1.ln ( 6 − x ) + ( x − )6 × 6 1 x + 1 − )g′( x) = ln (6 − x) − 1 + 1 = ln (6 − x -11ﺍﺴﺘﻨﺘﺎﺝ ﺍﻟﺩﻭﺍل ﺍﻷﺼﻠﻴﺔ ﻟﻠﺩﺍﻟﺔ : f f = )(x 2+ x 1 6 − ln ( 6 − )x ﻟﺩﻴﻨﺎ : − f )(x = 2− 1 − )g′( x : ﻤﻨﻪ ﻭ 6− x ﻭ ﻤﻨﻪ ﺍﻟﺩﻭﺍل ﺍﻷﺼﻠﻴﺔ hﻟﻠﺩﺍﻟﺔ fﻤﻌﺭﻓﺔ ﻜﻤﺎ ﻴﻠﻲ :h( x) = 2x − ln (6 − x) − ( x − 6) ln (6 − x) − x + c h( x) = x − (1 − x + 6) ln (6 − x) + c∈ h( x) = x − (7 − x) ln (6 − x) + c ; c√ (7 × (6 . √ (5 √ (4 . × (3 ﺍﻟﺘﻤﺭﻴﻥ.. 16 √ (2 √ (1 . × (10 √ (9 . × (8 ﺍﻟﺘﻤﺭﻴﻥ 17 (1ﺤل ﻜل ﺍﻟﻤﻌﺎﺩﻻﺕ ﻭ ﺍﻟﻤﺘﺭﺍﺠﺤﺎﺕ : )log6 = logx + log ( x − 1 ﺘﻜﻭﻥ ﺍﻟﻤﻌﺎﺩﻟﺔ ﻤﻌﺭﻓﺔ ﻤﻥ ﺃﺠل x > 0 :ﻭ x − 1 > 0 ﻭ ﻤﻨﻪ x > 1ﻭ ﻋﻠﻴﻪ ﻓﺎﻟﻤﻌﺎﺩﻟﺔ ﻤﻌﺭﻓﺔ ﻋﻠﻰ ∞ 1;+ﻭ ﺍﻟﻤﻌﺎﺩﻟﺔ ] [( )1 ﺘﻜﺎﻓﺊ logx ( x − 1) = log6 :ﻭ ﻫﻲ ﺘﻜﺎﻓﺊ x ( x − 1) = 6 :
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