trigonometry evaluate

[past dock]

GabeDoubleU

[surreal dove]

u have to find cos pi/5 and there are ways to find it but my fav 1 is
taking x = pi/10
so we can say cos(5x) = cos(3x+2x) = 0
now we do cos (a+b) for 3x,2x and we get what 3x is which is cos(pi/5)
then simplify the above to pi/5

[analog ravine]

yea i thought of that

wanted a simpler way

figured it out

tysm!