CEE Kerala Engineering CEE Kerala Engineering Solved Paper-2008

  • question_answer
    \[{{\int{(\sin x-\cos x)}}^{4}}(\sin x+\cos x)dx\]is equal to

    A)  \[\frac{\sin x-\cos x}{5}+c\]

    B)  \[\frac{{{(\sin x-\cos x)}^{5}}}{5}+c\]

    C)  \[\frac{{{(\sin x-\cos x)}^{4}}}{4}+c\]

    D)  \[\frac{{{(\sin x+\cos x)}^{5}}}{5}+c\]

    E)  None of the above

    Correct Answer: B

    Solution :

    Let\[I=\int{{{(\sin x-\cos x)}^{4}}}(\sin x+\cos x)dx\] Put  \[sin\text{ }x-cos\text{ }x=t\] \[\Rightarrow \]\[(\cos x+\sin x)dx=dt\] \[\therefore \]\[I=\int{{{t}^{4}}dt}=\frac{{{t}^{5}}}{5}+c\]                 \[=\frac{{{(\sin x-\cos x)}^{5}}}{5}+c\]


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