Cos(270°) = 0
Cosine — the x-coordinate of the corresponding unit-circle point, or adjacent/hypotenuse in a right triangle.
How to derive cos(270°)
At 270° the unit-circle point is (0, −1). Cosine = x = 0, which is also why tan(270°) is undefined.
Unit-circle context
The angle 270° corresponds to 3π/2 radians and sits on an axis on the unit circle.
Its reference angle is 90°, which is why cos(270°) shares its absolute value with cos(90°).
Other trig values at 270°
Related cos values
Frequently asked
- What is the exact value of cos(270°)?
- The exact value is 0. Its decimal approximation is 0.
- How do you derive cos(270°)?
- At 270° the unit-circle point is (0, −1). Cosine = x = 0, which is also why tan(270°) is undefined.
- What is 270° in radians?
- 270° equals 3π/2 radians (multiply degrees by π/180).
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