`int_(-a)^(a)log((a-x)/(a+x))dx=?`A. `2a`B. `a`C. `0`D. `1`

1.	`int_(-a)^(a)log((a-x)/(a+x))dx=?`A. `2a`B. `a`C. `0`D. `1`
Answer» `f(x)=log((a-x)/(a+x))`. `impliesf(-x)=log((a+x)/(a-x))=log{((a-x)/(a+x))^(-1)}=-log((a-x)/(a+x))=-f(x)` `:.f(x)` is odd and hence `I=0`.

Discussion

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