# Math Help - Evaluating trig questions

1. ## Evaluating trig questions

Hi
Can someone explain to be how you would simplify the following questions:
1) $sin^{-1}(cos\frac{5\pi}{6})$

2) $tan(sin^{-1}(\frac{-\sqrt2}{2}))$

P.S

2. just evaluate the expression inside the parenthesis and then you'll have a trig function of a number, which you can then evaluate again...

do you know how the inverse trig functions work in terms of domain restrictions?

3. ok thanks i think i know how to do it now.