Sin 142 Degrees

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

What is sin 142°?

Answer

sin 142° ≈
0.6157

Angle in radians: 142° = 71π/90. The point of the angle is in quadrant II, where sine is positive.

≈ — rounded to 4 decimal places. sin 142° can't be written with square roots: 142° is not a multiple of 3°.

sin 142° = sin(180° − 38°) = sin 38° ≈ 0.6157

P(cos 142°, sin 142°) ≈ (−0.7880, 0.6157)

xyOP

P(cos 142°, sin 142°) ≈ (−0.7880, 0.6157)

Highlighted: the projection on the y-axis — sine, y ≈ 0.6157.

All four functions of 142°
FunctionExact valueDecimal
sin 142°—≈ 0.6157
cos 142°—≈ −0.7880
tan 142°—≈ −0.7813
cot 142°—≈ −1.2799

Reference angle: sin 38° ≈ 0.6157

See Also

Recalculate with different values ↑

Sine of nearby angles

Anglesin
134°≈ 0.7193
135°√2/2
140°≈ 0.6428
142°≈ 0.6157
144°√(10 − 2√5)/4
145°≈ 0.5736
150°1/2

FAQ

What is sin 142°?

sin 142° ≈ 0.6157

Why does sin 142° 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°. 142° is not, so no such exact form exists; the value is used as a decimal: sin 142° ≈ 0.6157.

Why does a calculator show −0.5878 for sin 142?

The calculator is in radian mode (RAD): it takes sin 142 as the sine of 142 radians, sin 142 rad ≈ −0.5878. Switch it to degrees (DEG): sin 142° ≈ 0.6157. In radians the value is never undefined: π is irrational, so a whole number of radians never lands exactly on an axis.

See Also