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MUDIT (614)

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Olaaa!! Perrrfect answer. 110  [142 rates]

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i put x=tan@ so dx=sec^2@d@
and hence the expression becomes as follows tan@ln(tan@)sec^2@/sec^4@
which finally gives as d@tan@ln(tan@)/1+tan^2@
now since x=tan@ the limits change and go from 0 to pie/2.
now apply that theorum of f(a+b-x)=f(x)
so the original expression changes to as follows
cot@ln(cot@)/1+cot^2@ and now let usince tan@ = 1/cot@ we use this in that result and we get -tan@ln(tan@)d@/1+tan^2@
so addin up both the integrals 2I = 0 and hence the ans is 0
try it outyourself. please correct me if i am wrong or nudge me if you have any doubts

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