# Sine & Cosine Functions: Principle and Paired Solutions

- Author:
- St Davids College Maths Team

Use the check box to select a trigonometric function to investigate. This sheet works best when only one function is selected.
Use the slider to investigate the relationship between the principle solution you obtain on your calculator (alpha) and the paired solution (beta) that form the basis of finding all other solutions for the sine and cosine functions.

This sheet should allow you to use general relationships between principle and paired solutions for sine and cosine without the need for the graphs or CAST diagrams.