Cos 60 Degrees

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

What is cos 60°?

Answer

cos 60° =
1/2 = 0.5

Angle in radians: 60° = π/3. The point of the angle is in quadrant I, where cosine is positive.

P(cos 60°, sin 60°) = (1/2, √3/2)

Half of an equilateral triangle with side 1: the hypotenuse is 1 and the leg opposite 30° is 1/2.

cos 60° = 1/2

xyOP

P(cos 60°, sin 60°) ≈ (0.5, 0.8660)

Highlighted: the projection on the x-axis — cosine, x = 0.5.

All four functions of 60°
FunctionExact valueDecimal
sin 60°√3/2≈ 0.8660
cos 60°1/20.5
tan 60°√3≈ 1.7321
cot 60°√3/3≈ 0.5774

See Also

Recalculate with different values ↑

Cosine of nearby angles

Anglecos
57°≈ 0.5446
58°≈ 0.5299
59°≈ 0.5150
60°1/2
61°≈ 0.4848
62°≈ 0.4695
63°≈ 0.4540

FAQ

What is cos 60°?

cos 60° = 1/2 = 0.5

How to remember sin 30°, sin 45° and sin 60°?

Write them as √1/2, √2/2, √3/2: sin 30° = 1/2, sin 45° = √2/2, sin 60° = √3/2. Cosines are the same numbers in reverse order: cos 30° = √3/2, cos 45° = √2/2, cos 60° = 1/2; tan = sin / cos and cot = cos / sin. Here: cos 60° = 1/2 = 0.5.

Why does a calculator show −0.9524 for cos 60?

The calculator is in radian mode (RAD): it takes cos 60 as the cosine of 60 radians, cos 60 rad ≈ −0.9524. Switch it to degrees (DEG): cos 60° = 1/2 = 0.5. In radians the value is never undefined: π is irrational, so a whole number of radians never lands exactly on an axis.

See Also