Question

Find all the angles between 0° and360° which satisfy: 2sin^2 y - 3cos y = 0?

Answer 1

substituting ... 2[1 - cos^2(y)] - 3 cos(y) = 0 ... -2 cos^2(y) - 3 cos(y) + 2 = 0

solve the quadratic for cos(y) and fill in the angles