Thread: solution to trig

determine the fundamental solution set of sin x = sin 5x

Originally Posted by maeca

determine the fundamental solution set of sin x = sin 5x

Case 1: .

Case 2: .

Solve for x in each case.

is sinA + sin B = 2 sin ((A+B)/2) cos ((A-B)/2)

Originally Posted by maeca

is sinA + sin B = 2 sin ((A+B)/2) cos ((A-B)/2)

Yes. And I know what you're thinking. That's another way of solving the problem.

But the relevant formula for this question is

sinA - sin B = 2 sin ((A-B)/2) cos ((A+B)/2)

i would like to ask another question.
how can i express tan x/(1-2sin x + 3 cos x) in terms of tan(x/2)
thanks for answering my questions...

Originally Posted by maeca

i would like to ask another question.
how can i express tan x/(1-2sin x + 3 cos x) in terms of tan(x/2)
thanks for answering my questions...

Read this: PlanetMath: Weierstrass substitution formulas

By the way: Questions unrelated to the original questions should be posted as a new thread.