Sin(15°) = (√6 − √2)/4
Sine — the y-coordinate of the corresponding unit-circle point, or opposite/hypotenuse in a right triangle.
How to derive sin(15°)
Apply the difference formula sin(45° − 30°) = sin45°cos30° − cos45°sin30° = (√2/2)(√3/2) − (√2/2)(1/2) = (√6 − √2)/4.
Unit-circle context
The angle 15° corresponds to π/12 radians and sits Quadrant I on the unit circle.
Other trig values at 15°
Related sin values
Frequently asked
- What is the exact value of sin(15°)?
- The exact value is (√6 − √2)/4. Its decimal approximation is 0.25882.
- How do you derive sin(15°)?
- Apply the difference formula sin(45° − 30°) = sin45°cos30° − cos45°sin30° = (√2/2)(√3/2) − (√2/2)(1/2) = (√6 − √2)/4.
- What is 15° in radians?
- 15° equals π/12 radians (multiply degrees by π/180).
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