1. The problem statement, all variables and given/known data Just like my title says, we are to prove the trig identity sin^2x+cos^2x=1 using the Euler identity. 2. Relevant equations Euler - e^(ix) = cosx + isinx trig identity - sin^2x + cos^2x = 1 3. The attempt at a solution I tried solving the Euler for sinx and cosx, then plugging it into the trig identity. I just ended up with something really sloppy with multiple i's left over. I also tried squaring Euler and manipulating values that way to get an answer, but that just ended up really sloppy as well. If anyone has any tips, I'd really appreciate it. I spent about 30mins on this now and am just at a loss.