Unit 4 - Trigonometric Identities

Reciprocal Identity

Trig identities defining cosecant, secant, and cotangent in terms of sine, cosine, and tangent.

Identity

an equation having an infinite number of solutions; equation where left side is equal to right side

Establishing Identity

prove one side is equivalent to the other side of an equation, proof of identity

Even/Odd Identities

sin(-x) = - sin x cos(-x) = cos x tan (-x) = - tan x csc (-x) = - csc x sec (-x) = sec x cot (-x) = - cot x

Cofunction

the trigonometric function of the complement of an angle or arc.

Verifying Identity

to prove that both sides of an equation are equal for all values of the variable

Proving Identity

using logical steps to show that one side of an equation can be transformed to the other side