Need help with a double angle question

If cos2x=12/13 and 2x is in the first quadrant, evaluate the six trigonometric functions for x, without your calculator. The answer is:

cos x= 5/√26; sec x=√26/5

sinx=1/√26; csc x=√26

tanx=1/5; cot x=5

How do I get these answers? Any help would be greatly appreciated.

Re: Need help with a double angle question

Do you know either the "double angle formulas" or the "half angle formulas"?

Re: Need help with a double angle question

since , then

sub in the value given for ...

Re: Need help with a double angle question

Thanks guys, I got it now.