Question

solve - sin^2 x=2 cos x-2

Answer 1

first subtract 2cosx and add 2 to both sides

Answer 2

so -sin^2 x-2cosx+2=0

Answer 3

then what?

Answer 4

use Pythagorean identity of trig

Answer 5

sin^2x+cos^2=1

Answer 6

The cos isnt squared though so that doesn't work

Answer 7

sin is squared no?
i didn't say cos

Answer 8

Yes but you can't use the sin^2 x+cos^2 x=1 identity unless the cos is squared

Answer 9

I didn't mean that. what i mean is
find -sin^2x in terms of cos^2x
you will have all th equation as cos only

Answer 10

oh so it's simply cos^2 x-1 to replace the sin^2?

Answer 11

but don't forget the negative sign that is partern with sin^2x

Answer 12

i figured it out thanks!

Answer 13

ok good, you are welcome