put losinx=t
so ur int bcums
t dt
so itz
t^2/2
so log sinx d whole squre /2
put losinx=t
so ur int bcums
t dt
so itz
t^2/2
so log sinx d whole squre /2
integrate it by parts
Take the 1st function as log sinx and 2nd function as cot x
USE
∫cotx=lnsinx
i hope u will get ur answer
if still doubt persists then ask again!!!!!!
(1/2)[(logsinx)2]pi/6pi/2=(1/2)[0-(log1/2)2]=-(log2)2/2
whats your doubt here