Trigonometric value

Sin(180°) = 0

Sine — the y-coordinate of the corresponding unit-circle point, or opposite/hypotenuse in a right triangle.

How to derive sin(180°)

sin(180°)=0sin(180°) = 0

At 180° the terminal side points along the negative x-axis. The unit-circle point is (−1, 0); sine = y-coordinate = 0, so sin(180°) = 0.

Unit-circle context

The angle 180° corresponds to π radians and sits on an axis on the unit circle.

Other trig values at 180°

Related sin values

Frequently asked

What is the exact value of sin(180°)?
The exact value is 0. Its decimal approximation is 0.
How do you derive sin(180°)?
At 180° the terminal side points along the negative x-axis. The unit-circle point is (−1, 0); sine = y-coordinate = 0, so sin(180°) = 0.
What is 180° in radians?
180° equals π radians (multiply degrees by π/180).

Need to solve any sin problem step by step?

Open the AI Trigonometry Solver — type or upload any problem, get step-by-step explanations free.