Identities

Use the following formulas:

1) Sin^2 theta + Cos^2 theta = 1

2)1 + Cos^2 theta = Csc^2 theta

3)1+ Tan^2 theta = Sec^2 theta

Steps..

• Algebra
• Identities, try pythagorean, then move to Sin & Cos form, if that will help
• Algebra
• Continue 1-3

Ex: Sec X - Sin X Tan X

1) Sec = 1/cos then you are going to have to subtract that from Sin X

2) Multiply by Sin X/ Cos X

3) You are going to end up with 1/Cos X - Sin^2 X/ Cos X = 1- Sin ^2 X/ Cos X

4) Use the formula (Sin^2+Cos^2=1)

5) Your final step will be Cos^2X/CosX = Cos X