Question

Use a calculator to find the approximate value of cos-1(0.78).

Answer 1

38.74

Explanation:

Hello, I think I can help you with this.

in a standard calculator you will find the inverse cosine function as the second function of the cosine key

so

`cosine\ inverse=cos^(-1) \\`

step 1

once the calculator is on, press the shift key and then the cosine key, then write the number and close the parenthesis, finally press the equal key

shift ⇒cos⇒0.78⇒)⇒=

in the display you will see( DEG mode)

`cos^(-1)(0.78)\\\ 38.7394246\\`

Now, approximate

38.7394246\≈38.74

Have a great day.