Help with trig proofs. [edit: one remaining]
I'm stumped on three problems that were assigned on a math project for Algebra II/Trig.
[SOLVED] 1) Express the following function as a single circular sinusoid.
2) Prove that if y1=a1*sin(bx) and y2=a2*cos(bx), then A is an element of the real number and B is an element of the real number such that a1*sin(bx)+a2*cos(bx)=Asin(k(x+B)). A should be in terms of a1 and a2, and there should be only one expression for B. Also, state what the constant k is equal to.
[SOLVED, YAY!] 3) Prove that:
I apologize for the bad formatting (don't know how to get MathType into the forum. )
Any help would be greatly appreciated.