acos

the `acos` function returns the arc cosine of x in radians.

you must include the math header to use the `acos` method.

call `acos` with a value between negative one and one.

the argument passed to `acos` must be in the range [-1, 1].

this library calculates the angle by applying the `acos` operation.

use the `acos` function to determine the angle from the cosine value.

the output of `acos` represents an angle in the range [0, pi].

many programs import `acos` directly from the standard math module.

the variable result stores the value returned by the `acos` call.

input values greater than 1 will cause the `acos` function to fail.

we used `acos` to solve the geometry problem regarding triangles.

the inverse cosine is calculated using the `acos` command in this language.