Question

3cos^2(x)-sin^2(x)=0

Answer 1

have to find the soultions on the interval [0, 2pi)

Answer 2

Use the identity cos^2(x)=1-sin^2(x) and you will have a problem in terms of sin^2(x)

Answer 3

thank you!

Answer 4

but that doesn't work out..
unless im doing it wrong..?

Answer 5

It goes:
3(1-sin^2(x))-sin^2(x)=0
3-3sin^2(x)-sin^2(x)=0
So
-4sin^2(x)=-3

Answer 6

okay.. so then sin(x)= sq root (3/4)
but sin never equals the sq root (3/4) on the unit circle?

Answer 7

never mind. that would be the same as sq root (3) / 2 duhhh! hah i figured it out. thank you!!