Simplifying Trigonometric Expressions (Using Identities)

How to work with Trigonometric Identities. We discuss the reciprocal identities, quotient identities, pythagorean identities, cofunctions, and even and odd identities.

0:08 What is a Trig Identity
0:26 Formulas for Reciprocal Identities
0:44 Pythagorean Identities
1:17 CoFunction Identities
1:37 Even and Odd Identities
2:13 Understanding the Even and Odd Identities
2:49 Understanding CoFunctions
3:50 Example 1 Simplify the Trig Expression sin(x)sec(x)
4:28 Example 2 Simplify the Trig Expression by Factoring sec^4(x) - tan^4(x)
6:01 Example 3 Simplify sin(x)(cot(-x))
7:06 Example 4 Verify the Trig Identity sinx(csc(pi/2 - x)) = tanx
7:25 Tips for Verifying Trig Identities
9:01 Example 5 Sin^2(x) - sin^4(x) = cos^2(x) - cos^4(x)
9:03 More Hints on How To Solve Trig Identities

Related Videos:

Verifying Trig Identities Examples

Solving Trig Equations

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