Cos 88 Degrees

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

What is cos 88°?

Answer

cos 88° ≈
0.0349

Angle in radians: 88° = 22π/45. The point of the angle is in quadrant I, where cosine is positive.

≈ — rounded to 4 decimal places. cos 88° can't be written with square roots: 88° is not a multiple of 3°.

P(cos 88°, sin 88°) ≈ (0.0349, 0.9994)

xyOP

P(cos 88°, sin 88°) ≈ (0.0349, 0.9994)

Highlighted: the projection on the x-axis — cosine, x ≈ 0.0349.

All four functions of 88°
FunctionExact valueDecimal
sin 88°—≈ 0.9994
cos 88°—≈ 0.0349
tan 88°—≈ 28.6363
cot 88°—≈ 0.0349

See Also

FAQ

What is cos 88°?

cos 88° ≈ 0.0349

Why does cos 88° 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°. 88° is not, so no such exact form exists; the value is used as a decimal: cos 88° ≈ 0.0349.

Why does a calculator show 0.9994 for cos 88?

The calculator is in radian mode (RAD): it takes cos 88 as the cosine of 88 radians, cos 88 rad ≈ 0.9994. Switch it to degrees (DEG): cos 88° ≈ 0.0349. In radians the value is never undefined: π is irrational, so a whole number of radians never lands exactly on an axis.