Sin 270 Degrees

Sin, Cos, Tan, Cot of an Angle
Function
Angle (°)

What is sin 270°?

Answer

sin 270° =
−1

Angle in radians: 270° = 3π/2. The point of the angle is on the y-axis: (0, −1).

P(cos 270°, sin 270°) = (0, −1)

xyOP

P(cos 270°, sin 270°) = (0, −1)

Highlighted: the projection on the y-axis — sine, y = −1.

All four functions of 270°
FunctionExact valueDecimal
sin 270°−1−1
cos 270°00
tan 270°undefined—
cot 270°00

Reference angle: sin 90° = 1

See Also

Recalculate with different values ↑

Sine of nearby angles

Anglesin
240°−√3/2
252°−√(10 + 2√5)/4
255°−(√6 + √2)/4
270°−1
285°−(√6 + √2)/4
288°−√(10 + 2√5)/4
300°−√3/2

FAQ

What is sin 270°?

sin 270° = −1

Why is sin 270° equal to −1?

The point of 270° on the unit circle is (0, −1), and sine is its the y-coordinate, so sin 270° = −1.

Why does a calculator show −0.1760 for sin 270?

The calculator is in radian mode (RAD): it takes sin 270 as the sine of 270 radians, sin 270 rad ≈ −0.1760. Switch it to degrees (DEG): sin 270° = −1. In radians the value is never undefined: π is irrational, so a whole number of radians never lands exactly on an axis.

See Also