Question

verify the identity
cos(x+ pi/2) = - sin x

Answer 1

hint:

cos(A+B) = cos(A)cos(B) - sin(A)sin(B)

Answer 2

^---- hint too big

Answer 3

what do you mean dan815?

Answer 4

\[\large cos (\color{red}A +\color{blue}B) = cos(\color{red}A)cos(\color{blue}B) - sin(\color{red}A)sin(\color{blue}B)\]\[\large cos(\color{red}x+ \color{blue}{\pi/2})= \]

Answer 5

I love these formulas cause you can apply COLORS!!!