Question

How do you evaluate using a calculator of `arcsin(-0.6821)`?

Answer 1

`223^@; 317^@`

Explanation:

Using both calculator and unit circle.
Calculator gives:
sin x = - 0.6821 --> arc `x = - 43^@` or x = 317^@ (co-terminal)
Unit circle gives another arc x that has the same sin value:
`x = 180 + 43 = 223^@`
Answers for `(0, 360)`:
`223^@; 317^@`