39. 1ഽ2(x - 1)/x^3 dx = ...
a. - 1 1/16
b. 1/8
c. 1
d. 1 1/2
e. 21/8
Jawaban :
1ഽ2(x - 1)/x^3 dx
= 1ഽ2(x - 1) . x^-3 dx
= 1ഽ2(x^-2 - x^-3) dx
= [1/(-2 + 1) x^(-2 + 1) - 1/(-3 + 1) x ^ (-3 + 1) ]12
= [ -x^-1 - 1/(-2) x ^ -2 ]12
= [ - 1/x + 1/2 . 1/x^2 ]12
= ( - 1/2 + 1/2 . 1/2^2) - (- 1/1 + 1/2 . 1/1^2)
= ( - 1/2 + 1/2 . 1/4) - (- 1 + 1/2 )
= (- 1/2 + 1/8) - (- 1/2)
= - 1/2 + 1/8 + 1/2
= 1/8
Jawaban : B
No comments:
Post a Comment