Question

Solve these over the domain 0≤a≤2pi:
3cos^2a-5cosa-1=3sin^2a
and 1/cos^2a+1-3tan^2a=0

I'm not sure what to do for either of these questions, can someone please help?

Answer 1

umm i think graph it

Answer 2

between that interval

Answer 3

oh nvm

Answer 4

Don't graph anything.

Hint: \(\sin^{2}(x) = 1 - \cos^{2}(x)\)

Answer 5

do it like quadratic

Answer 6

they just want the solution to be in that interval

Answer 7

Ok so like 3cos^2a-5cosa-1=3(1-cos^2(a))?

Answer 8

ya and then just put it on 1 side and finish like ud solve a quadratice equation

Answer 9

Like 3cos^2a-5cosa-1-3-3cos^2(a)=0?

Answer 10

ya but +3cos^2

Answer 11

3cos^2a-5cosa-1-3+3cos^2(a)=0?
6cos^2a-5cosa-4=0