Question

2sin^2(x)=2+cos(x)............i am so lost

Answer 1

sub.s in sin^2(x) = 1-cos^2(x)

I guess you don't really need the steps with 'u=cos(x)' in this problem...

Answer 2

2(1-cos^2(x) ) = 2+cos(x)
2 -2cos^2(x) = 2+cos(x)
-2cos^2(x) = cos(x)
cos(x) = -1/2


converting it into a quadratic will come in handy down the road though, so keep it in mind....

Answer 3

how did you get rid of -2cos^2(x)

Answer 4

divide both sides by -2cos(x)