prove that sin sqared pie/6+ cos sqared pie/3-tansqare pie/4=1/2 in trigonometry

Answer 1

GRR! PI, not pie!

sin pi/6 = cos pi/3 = 1/2
tan pi/4 = 1
so, we have

1/4 + 1/4 - 1 = -1/2

I suspect a typo