I need to find all solutions of the given equations for the indicated interval. Round solutions to three decimal places if necessary.

Question

1.) 3sin(x)+1=0, x within [0,2pi)
2.) 2sin(sq'd)(x)+cos(x)-1=0, x within R
3.) 4sin(sq'd)(x)-4sin(x)-1=0, x within R
4.) sin(x)+1=cos(x), x within [0, 2pi) -check for extraneous solutions.

Answer 1

on 2 remember that sin^2 x = 1-cos^2 x, then use the quadratic formula,or factor.
on 3, factor
on 4,try squaring both sides, then substitue to get rid of the cos^2