Sin(135°) = √2/2
Sine — the y-coordinate of the corresponding unit-circle point, or opposite/hypotenuse in a right triangle.
How to derive sin(135°)
135° is in quadrant II. Reference angle = 180° − 135° = 45°, and sine is positive in quadrant II, so sin(135°) = +sin(45°) = √2/2.
Unit-circle context
The angle 135° corresponds to 3π/4 radians and sits Quadrant II on the unit circle.
Its reference angle is 45°, which is why sin(135°) shares its absolute value with sin(45°).
Other trig values at 135°
Related sin values
Frequently asked
- What is the exact value of sin(135°)?
- The exact value is √2/2. Its decimal approximation is 0.70711.
- How do you derive sin(135°)?
- 135° is in quadrant II. Reference angle = 180° − 135° = 45°, and sine is positive in quadrant II, so sin(135°) = +sin(45°) = √2/2.
- What is 135° in radians?
- 135° equals 3π/4 radians (multiply degrees by π/180).
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