# How do you do simplify #cos [sec ^-1 (-5)]#?

##### 1 Answer

#### Explanation:

**Finding the value of the Composition:**

Lets being to solve the equation by working on the inside. Immediately we can see that **not** be *negative*. and "1" serves as the x-value in this equation.

**Note:** The inverse of cosine (secant) is restricted between *sin* instead of cos because the y-value would become negative and give you a wrong answer).

Now cosine is

This is not a special angle so leave the answer as a improper fraction or decimal. Whatever your instructor prefers. :)