Recent content by joshnfsmw

ok then how to we get rid of the extra cosines that were introduced in the formula?

That's the puzzling part. So we let z=(cosx+jsinx)^n ?

De Moivre's Theorem: [cos(x)+jsin(x)]^n= cos(nx)+jsin(nx), where j is the imaginary unit This is all that the question gave. It asks to prove it, so you don't need any complex variable. Like for part a), [(1-z)(z+z^3+z^5+z^7+z^9+z^11)+z^13]*[(1+z)/(1+z)] = (z+z^14)/(1+z) (shown)

De Moivre's theorem for Individual sine functions. Need urgent help! Hey guys I need some help with this question! I've only been able to do the first part by factorising out (1-z) for the first 12 terms and then multiplying (1+z)/(1+z) to the whole equation. For part b), I am totally lost...