JEE Main & Advanced Mathematics Definite Integration Question Bank Properties of Definite Integration

  • question_answer
    \[\int_{0}^{\pi /2}{\frac{\sin x}{\sin x+\cos x}\,dx}\] equals [RPET 1996; Kerala (Engg.) 2002]

    A)                 \[\frac{\pi }{2}\]              

    B)                 \[\frac{\pi }{3}\]

    C)                 \[\frac{\pi }{4}\]              

    D)                 \[\frac{\pi }{6}\]

    Correct Answer: C

    Solution :

               \[I=\int_{0}^{\pi /2}{\frac{\sin x.dx}{\sin x+\cos x}}=\int_{0}^{\pi /2}{\frac{\cos x.dx}{\cos x+\sin x}}\], \[\,\,\left( \because \int_{0}^{a}{f(x)dx=\int_{0}^{a}{f(a-x)dx}} \right)\]                                 \[2I=\int_{0}^{\pi /2}{dx}\Rightarrow I=\frac{\pi }{4}\].


You need to login to perform this action.
You will be redirected in 3 sec spinner