Question

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

Answer 1

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 `"asin"`
- one uses `"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.