Evaluate of each of the following integrals (1-15): `int_(-a)^a1/(1+a^x)dx ,a>0`

Evaluate of each of the following integral: int_(-pi//3)^(pi//3)1/(1+e^x)dx

Evaluate of each of the following integrals (1- 15): int_(0)^(2 pi)log(sec x+tan x)dx

Evaluate each of the following integral: int_(-1)^1x|x|dx

Evaluate each of the following integral: int_(-2)^1(|x|)/x dx

Evaluate each of the following integral: int_2^3 1/x dx

Evaluate each of the following integral: int_0^3 1/(x^2+9)dx

Evaluate of each of the following integrals (1-x^((1)/(3))15):int_(0)^(7)((x^((1)/(3)))/(x^((1)/(3))+(7-x)^((1)/(3))))dx])

Evaluate each of the following integral: int_0^1x\ e^x^2dx

Evaluate each of the following integral: int_0^1(2x)/(1+x^2dx)

Evaluate the following integrals: int_(-1)^(1)e^(|x|)dx