Find all possible solutions in the range 0°≤ x ≤ 180° of the following equations:
(a) cos x = sqrt(2) / 2
(b) tan x = sqrt(3) / 3
(c) sin x = sin60°
(d) cos x = -1/2
(e) sin x = -1/2
find the reference angle in QI.
only sin x is positive in QII.
For example,
cos x = √2/2
x = 45°
Since cos x < 0 in QII, that is the only solution.
Work the others in like wise.