Does Trigonometric Functions Have Units?

Trigonometric functions don't "preserve" units. The expression under a trigonometric function must be dimensionless and so is the value of a trigonometric function.

What are the units of trigonometric functions?

0.5.

There are two commonly used units for measuring angles, degrees and radians, and so there are two commonly used versions of the trigonometric functions. There's sinx ⁡ where x is in degrees, and there's sinx ⁡ where x is in radians.

Are trigonometric functions dimensionless?

The arguments of any of the standard mathematical functions such as trigonometric functions (such as sine and cosine), logarithms, or exponential functions that appear in the equation must be dimensionless. These functions require pure numbers as inputs and give pure numbers as outputs.