Lesson 3 Summary

 

In Focus you read about two race cars that were identical in every way other than colour. This analogy was used to describe trigonometric identities, equations with sides that look different but generally act the same. An identity is a mathematical equation that is true for any permissible value. In this lesson you worked with Pythagorean and reciprocal identities as well as some other less common identities. It is possible to verify an identity both graphically and numerically when given a potential identity.

 

Identities can be used to simplify some expressions; if one side of the identity appears in an expression, the other side of the identity can replace it. When simplifying using an identity, any restrictions on the identity also apply to the simplified expression.

 

In the next lesson you will learn some new trigonometric identities and use identities to help solve trigonometric equations.