Tan 142 Degrees

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

What is tan 142°?

Answer

tan 142° ≈
−0.7813

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

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

tan 142° = tan(180° − 38°) = −tan 38° ≈ −0.7813

tan 142° = sin 142° / cos 142° ≈ −0.7813

xyOP

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

T(1, tan 142°) ≈ (1, −0.7813) — where line OP meets the line x = 1, on the extension of the ray beyond O (dashed).

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: tan 38° ≈ 0.7813

See Also

Recalculate with different values ↑

Tangent of nearby angles

Angletan
134°≈ −1.0355
135°−1
140°≈ −0.8391
142°≈ −0.7813
144°−√(5 − 2√5)
145°≈ −0.7002
150°−√3/3

FAQ

What is tan 142°?

tan 142° ≈ −0.7813

Why does tan 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: tan 142° ≈ −0.7813.

Why does a calculator show 0.7266 for tan 142?

The calculator is in radian mode (RAD): it takes tan 142 as the tangent of 142 radians, tan 142 rad ≈ 0.7266. Switch it to degrees (DEG): tan 142° ≈ −0.7813. In radians the value is never undefined: π is irrational, so a whole number of radians never lands exactly on an axis.

See Also