Question

Prove 2cos^2x=1+sinx

Answer 1

does the first 2 go on the entire 'cos^2x'

Answer 2

Yes

Answer 3

OK so what you have is
cos^2x+cos^2x=1+sinx

(did you mean sin^2x?)

Answer 4

No

Answer 5

I think you can disprove this.
Let x=0.
Are both sides equal when you let x=0?

Answer 6

i think he means to solve that and not prove...

Answer 7

I have to prove this with identities. I think maybe the instructor put in the number incorrectly.

Answer 8

you can prove it is not an identity.

Answer 9

I don't think you can prove this using identities.

Answer 10

2(cos^2x)=1+sinx
cos^2x=1-sin^2x
therefore
2(1-sin^2x)=1+sinx
-2sin^2x=-1+sinx

no, i don't know, not yet, but I brought it down into sines

Answer 11

Lets say the following!
Let Sinx=a
@karenmfarmer, can you solve now?

Answer 12

@karenmfarmer, do you know how to substitute a for sinx into the above equation?

Answer 13

I can solve the problem is that I have to prove using identity. I believe the instructor may have entered it wrong. Thanks for the help

Answer 14

Anytime!
Again, this is not something that you can prove, this is a solving problem.