# How do you do inverse trig functions on the calculator for example sinθ = 0.4?

Nov 29, 2015

It will depend upon your calculator. Look for one of the following: sin^(-1), arcsin, or asin.

#### Explanation:

Typically this would be a "2nd function" key,
so you would hit

• "2nd Function",
• ${\sin}^{- 1}$ (or whatever you have),
• the value (in this case (0.4),
• then the "enter" or "=" key.

Digging through the drawers of my desk I found 4 old calculators; combining that with Excel that I often use as a calculator:
- two use ${\sin}^{- 1}$
- two use $\text{asin}$
- one uses $\text{arcsin}$

To further confuse matters one of the ones that uses ${\sin}^{- 1}$ returns a value in degrees and the other four return values in radians.