Math

Half-Angle Calculator

sin(θ/2) and cos(θ/2) from θ in degrees (principal square roots with sign of the half-angle in (−90°, 90°)).

sin(θ/2)

cos(θ/2)

This free Half-Angle Calculator covers sin(θ/2) and cos(θ/2) from θ in degrees (principal square roots with sign of the half-angle in (−90°, 90°)).

Half-angle formulas take square roots of (1±cos θ)/2. Other math tools are linked below.

Half-Angle Calculator — how it works

sin(θ/2) and cos(θ/2) from θ in degrees (principal square roots with sign of the half-angle in (−90°, 90°)). Typical inputs are θ (°). How it works beside the form states the identity the Half-Angle Calculator applies.

FAQ

How do I use the Half-Angle Calculator?

Open the Half-Angle Calculator, fill θ (°), and read the result. Half-angle formulas take square roots of (1±cos θ)/2.

What formula does the Half-Angle Calculator use?

The Half-Angle Calculator uses the identity in How it works. In words: Half-angle formulas take square roots of (1±cos θ)/2.

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