there are 3 some questions from my Calculus homework that are giving me real head ache ! , please help dudes

have to get the integral of the followings

1. dx / ( 2e^x ) * sqr root ( 1 - e^2x ) INDEFINITE

2. { sqr root [ (1 - x^2)^3 ] } dx [0,1] DEFINITE

3. { x^3 * sin^2 * x / x^4 + 2x^2 + 1 } dx [-5,5] DEFINITE

please write the way of how to do each question with formulas used, it would be very very nice of you ! thanks alot in advanced !