Verifying Trig Identities I. Guidelines for Verifying Trig Identities. A) Work with one side of the equation at a time. 1) Work with the more complicated side first. B) Look for opportunities to use the fundamental trig identities to replace terms with their identity form. C) Convert the trig functions into sine & cosine (cancel out). D) Try to factor out the GCF, or use any other factoring method. Add fractions (get a common denominator). Square or square root a side. Multiply one side by its conjugate pair. E) Note which trig words are in the final answer. Keep them when possible and cancel out unneeded trig works. F) Always try something. Even paths that lead to dead ends can provide insights.

Verifying Trig Identities II. Why do we verify trig identities? A) We can take complex trig functions and simplify them into easier to use forms by using trig identities. *B) Be aware that we are VERIFYING trig identities, so we cannot assume that both sides of the equation are equal. 1) This means we cannot use normal solving steps when verifying trig identities. We cannot use operations such as adding, subtracting, multiplying or dividing the same value to both sides of the equation. 2) We also cannot use cross multiplication nor squaring or square rooting both sides of the equation. Homework page 387 # 1 – 37 odd