Cos(0°) = 1
Cosine — the x-coordinate of the corresponding unit-circle point, or adjacent/hypotenuse in a right triangle.
How to derive cos(0°)
At 0° the unit-circle point is (1, 0). Cosine is the x-coordinate, so cos(0°) = 1 — the maximum value cosine ever takes.
Unit-circle context
The angle 0° corresponds to 0 radians and sits on an axis on the unit circle.
Other trig values at 0°
Related cos values
Frequently asked
- What is the exact value of cos(0°)?
- The exact value is 1. Its decimal approximation is 1.
- How do you derive cos(0°)?
- At 0° the unit-circle point is (1, 0). Cosine is the x-coordinate, so cos(0°) = 1 — the maximum value cosine ever takes.
- What is 0° in radians?
- 0° equals 0 radians (multiply degrees by π/180).
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