Definite Integration Question 49
Question: $ \int _{-\frac{1}{2}}^{\frac{1}{2}}{\cos x\ln \frac{1+x}{1-x}dx} $ is equal to
[AMU 2000]
Options:
A) 0
B) 1
C) 2
D) ln 3
Show Answer
Answer:
Correct Answer: A
Solution:
$ I=\int _{-1/2}^{1/2}{\cos x\ln ( \frac{1+x}{1-x} )dx} $
$ \cos x\ln ( \frac{1+x}{1-x} ) $ is an odd function, $ (\because $
$ f(-x)=-f(x) $ ) $ I=0 $ .
BETA
