Solution 14484: Using the Inverse Function or Reciprocal on the TI-30X IIS/B.
How do I perform the inverse function on my TI-30X IIS/B?
The inverse function is represented as x-1. The [x-1] key is located directly under the [SIN] key. Please refer to the example below for instructions on using the inverse function on the TI-30X IIS/B.
Please Note: The reciprocal of a number is needed whenever there is division by a fraction. Division by a fraction is actually multiplication by that fraction's reciprocal.
Example: Find the inverse of 3.
1) Press  [x-1] [ENTER].
The calculator will display .33333333333.
To show answer in fraction format:
1) Press  [x-1].
2) Press [2nd] [F◄►D] [ENTER].
Please see the TI-30X IIS/B guidebook for additional information.