Question

Question #7d714

Answer 1

`0.`

Explanation:

Let, `I=int_-4 ^ 4 x^3cos(e^x+1/e^x-1)dx`.

`:. I=int_ -4 ^4 x^3cos(e^x+e^-x-1)dx`.

Observe that the Integrand is an odd function, and recall that,

`f" is continuous over "[-a,a] (a>0) rArr int _-a^af(x)dx=0," if f is odd."`