Let f(x)=xcos 2 x f(-x)=(-x)cos 2 (-x) =-xcos 2 x =-f(x) Hence, f(x) is an odd function. Since, if f(x) is an odd function. Therefore, I=0.

Evaluate

Let

f(x)=xcos²x

f(-x)=(-x)cos²(-x)

=-xcos²x

=-f(x)

Hence, f(x) is an odd function.

Since, if f(x) is an odd function.

Therefore, I=0.