This are some problems from my practice i couldn't solve.. please help me :)

1. y= Ln e^4x - 1 / e^4x + 1

2. F(x) = (tan^2 x - x^2)^3

3. X + Ln x^2 y + 3y^2 = 2x^2 - 1

4. y= Ln(cos3x)

5. F(x) = (x+1)^1/2 - ln [1 + (x+1)^1/2]

And one integral!

(I need to solve this one by substitution) =/

1. |y^3(2y^2-3)dy