Several questions from my homework, any are appreciated. Thanks!

Solve:
1) sinx-tanx=0
2) 3csc^2x=4
Find all solutions within (0,2pi)
3) cos4x(cosx-1)=0
4) cos4x-7cos2x=8
Use inverse functions where necessary to find solutions from 0 to 2pi
5) sin^2x-2sinx=0
Find the exact value of the tangent of the angle
6) (25pi)/12=(11pi)/6+(pi/4)