Arcsin of 1

Arcsin, Arccos, Arctan, Arccot

What is arcsin(1)?

Answer

arcsin(1) =

90° = π/2

Range: arcsin x is an angle from −90° to 90°, so the answer is unique.

arcsin(1) is the angle α in [−90°, 90°] with sin α = 1.

α = arcsin(1) = 90°

P(cos 90°, sin 90°) = (0, 1)

P lies on the line y = 1 in the right half of the circle, where cos α ≥ 0; highlighted: sin α = 1.

arcsin(1) = 90° = π/2

Look in the table for the angle α in [−90°, 90°] with sin α = 1: it is 90°, or π/2 in radians.

The calculator is in radian mode (RAD) and gives the angle in radians: arcsin(1) = π/2 ≈ 1.5708 rad. In degrees (DEG) it is 90°.