# maths

posted by
**jake** on
.

Find the roots of z^6 + 1 and hence resolve z^6 + 1into read quadratic factors; deduce that

cos3x = 4[cos(x) -cos(pi/6)][(cos(x) -cos(pi/2)][(cos(x) -cos(5pi/6)]

posted by
**jake** on
.

Find the roots of z^6 + 1 and hence resolve z^6 + 1into read quadratic factors; deduce that

cos3x = 4[cos(x) -cos(pi/6)][(cos(x) -cos(pi/2)][(cos(x) -cos(5pi/6)]