Question

Sin2pieover13plus cos squared pie over 13 equals.

Answer 1

First off, it's "pi" not "pie."

sin 2pi/13 + cos^2 pi/13

cos^2 pi/13 = (1 + cos 2pi/13)/2

so we have

sin 2pi/13 + (1 + cos 2pi/13)/2

Hmmm. Is there somewhere in particular we're going with this?