Sin 8 Degrees

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

What is sin 8°?

Answer

sin 8° ≈
0.1392

Angle in radians: 8° = 2π/45. The point of the angle is in quadrant I, where sine is positive.

≈ — rounded to 4 decimal places. sin 8° can't be written with square roots: 8° is not a multiple of 3°.

P(cos 8°, sin 8°) ≈ (0.9903, 0.1392)

xyOP

P(cos 8°, sin 8°) ≈ (0.9903, 0.1392)

Highlighted: the projection on the y-axis — sine, y ≈ 0.1392.

All four functions of 8°
FunctionExact valueDecimal
sin 8°—≈ 0.1392
cos 8°—≈ 0.9903
tan 8°—≈ 0.1405
cot 8°—≈ 7.1154

See Also

Recalculate with different values ↑

Sine of nearby angles

Anglesin
5°≈ 0.0872
6°≈ 0.1045
7°≈ 0.1219
8°≈ 0.1392
9°≈ 0.1564
10°≈ 0.1736
11°≈ 0.1908

FAQ

What is sin 8°?

sin 8° ≈ 0.1392

Why does sin 8° have no exact value?

A trigonometric value of a whole number of degrees can be written with square roots only when the angle is a multiple of 3°. 8° is not, so no such exact form exists; the value is used as a decimal: sin 8° ≈ 0.1392.

Why does a calculator show 0.9894 for sin 8?

The calculator is in radian mode (RAD): it takes sin 8 as the sine of 8 radians, sin 8 rad ≈ 0.9894. Switch it to degrees (DEG): sin 8° ≈ 0.1392. In radians the value is never undefined: π is irrational, so a whole number of radians never lands exactly on an axis.

See Also