7.1 Verifying Trigonometric Identities

Trigonometric Expression- Contains symbols involving trigonometric functions.


When verifying an identity, there are 3 things to keep in mind:

• Reciprocal identities




• Tangent and cotangent identities

• Pythagorean identities

It's also important to remember to cancel out factors, don't cancel out terms.

It's easier to start with the more complicated side of the equation so you can transform it into the other side using basic identities.

Here's an example that was in our homework:

(sin(θ))4 +2(sin(θ))2(cos(θ))2 + (cos(θ))4 = 1

((sin(θ))2 + (cos(θ))2) ((sin(θ))2 + (cos(θ))2) = 1 -----------> FOIL

(1)(1) = 1 --------------->pythagorean identity

This section is basically all review and we've already learned how to do this, so I'm not sure what else to say. Sorry if this is slackerish!

Megan