You're kidding on #4, right? Don't those middle terms cancel each other and leave a much simpler problem?
1. 3cot^2 (x) - 1 = 0
My answer: pi/3, 2pi/3, 4pi/3, 5pi/3
2. 4cos^2 (x) - 1 = 0
My answer: pi/3, 2pi/3, 5pi/3, 4pi/3
3. 2sin (x) + csc (x) = 0
My answer: unknown lol
i got to the part: sin^2 (x) = -1/2
4. 4sin^3 (x) + 2sin^2 (x) - 2sin (x) = 1
(ahhhhhh)
Answer verification needed ASAP