Basic+Identities

=Basic Identities by: Marcus Brockington, Peter Johnston, Tom Simon, Zoe Benditt=

Things to know:

sin² + cos² = 1 1 + cot² = csc² 1 + tan² = sec²

sin = ¹/csc ••• cos = ¹/sec csc = ¹/sin ••• sec = ¹/cos tan = sin/cos ••• cot = cos/sin

Things to Remember:

- sin² ≠ sin, cos² ≠ cos, csc² ≠ csc, etc. • Squared identities, such as sin² + cos² = 1 cannot be used as sin + cos = 1

Don’t forget, you can factor & simplify!

Prove the Following identities:

1) (1/ 1-sec x) + (1/ 1+ sec x) = 2 cot^2 x

Answer: 2/ 1-tan ^2 = -2 cot^2 x

2) cot x( 1+tan^2 x)/(tan x) = csc^2 x

Answer: 1/sin^2 = csc^2

A video talking about Trigonometric Identities: media type="youtube" key="OLzXqIqZZz0" height="344" width="425"

Yet another video about Basic Identities: media type="youtube" key="OJz-fOzFbEc" height="344" width="425"

And finally, C is for Cookie. media type="youtube" key="BovQyphS8kA" height="344" width="425"