If anybody can help me with at least one of these I would be grateful.

1) the integral of (2e^x - 2e^-x)/[(e^x + e^-x)^2]

2) the integral of (x^2)/(x^2 +4)

3) The integral of (2x) divided by the square root of (4x-x^2)

4) The integral from pi/4 to pi/2 of (cosx)/(1+(sinx)^2)