Cot 180 Degrees

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

What is cot 180°?

Answer

cot 180°
is undefined

Angle in radians: 180° = π. The point of the angle is on the x-axis: (−1, 0).

sin 180° = 0, and cot = cos / sin: you can't divide by zero, so the value doesn't exist.

cot 180° = cos 180° / sin 180° = (−1) / 0

xyOP

P(cos 180°, sin 180°) = (−1, 0)

Line OP of 180° runs parallel to the line y = 1: they never meet, so cot 180° doesn't exist.

All four functions of 180°
FunctionExact valueDecimal
sin 180°00
cos 180°−1−1
tan 180°00
cot 180°undefined—

Reference angle: cot 0° is undefined

See Also

Recalculate with different values ↑

Cotangent of nearby angles

Anglecot
167°≈ −4.3315
175°≈ −11.4301
179°≈ −57.2900
180°undefined
195°2 + √3
198°√(5 + 2√5)
200°≈ 2.7475

FAQ

What is cot 180°?

cot 180° is undefined

Why does cot 180° not exist?

The point of 180° on the unit circle is (−1, 0): sin 180° = 0, and cot = cos / sin would divide by zero. On the unit circle line OP runs parallel to the line y = 1 and never meets it.

Why does a calculator show 0.7470 for cot 180?

The calculator is in radian mode (RAD): it takes cot 180 as the cotangent of 180 radians, cot 180 rad ≈ 0.7470. Switch it to degrees (DEG): cot 180° is undefined. In radians the value is never undefined: π is irrational, so a whole number of radians never lands exactly on an axis.

See Also