Find the angle whose sine equals a given value, with principal value in degrees or radians.
The inverse sine (arcsin) returns the angle whose sine equals x. The principal value is in [−90°, 90°] or [−π/2, π/2]. The domain is [−1, 1].
Inverse sine
θ = arcsin(x), where −1 ≤ x ≤ 1
arcsin(0.5) = 30°, because sin(30°) = 0.5.
Sine never exceeds 1 or drops below −1, so no angle exists whose sine is outside that range.