VERIFYING TRIGONOMETRIC IDENTITIES
The fundamental identities are used to establish additional
relationships among trigonometric functions.
The fundamental identities consist of reciprocal identities, quotient identities, and Pythagorean identities.
Example 1
Verify the identity:
Solution:
An often used strategy in verifying identities is to write the expression
in terms of sine and cosine alone.
The left side is more complicated so we start working with this side.
Example 2
Verify the identity:
Solution:
Another way to verify an identity is to work
separately with both sides and show that the two sides are
identical to the same expression. This method is used when working
on one side alone does not seem to work.
We start working with the left side.
Try these problems
QUESTIONS
Verify the identity.
ANSWERS
