find, to the nearest minute, the solution set of 1- sin x = 3 cos^2 x over the domain 0 degrees to 360 degrees
For this and the others you must know your basic identities.
In this case
sinx = 3cos^2x
sinx = 3(1-sin^2x)
3sin^2x + sinx - 3 = 0
by the formula
sinx = .84713 or some number < -1, which is not possible
if sinx = .84713 (x in I or II)
x = 57.9006° or 122.099°
x = 57° 54' or 122° 6'