Math

Evaluating inverse trig.

Definition

Evaluating inverse trig functions means finding the angle whose trig value equals a given number. Each inverse function has a restricted range to ensure a unique output: arcsin and arctan return angles in [-π/2, π/2], and arccos returns angles in [0, π].

Examples

Real-world.

  • 1 arcsin(1/2) = π/6 (or 30°) because sin(30°) = 1/2
  • 2 arccos(-1) = π because cos(π) = -1
  • 3 arctan(1) = π/4 because tan(45°) = 1
Key Fact

arcsin range: [-π/2, π/2]; arccos range: [0, π]; arctan range: (-π/2, π/2)

Studied in

1 unit use this concept.