Express sin(5theta) in terms of sin(theta) and powers of sin(theta) only.

Consider the expression (cos(theta) + i*sin(theta))5 . (Where theta a real parameter).By De Moirve's theorem, we know this expression is equivalent to cos(5theta) + i sin(5theta).We can also apply the binomial expansion to this expression and sort into real and imaginary components.We can then equate these two expressions we have found and compare imaginary components to obtain the required solution.This is best written out by hand.

PF

Related Further Mathematics A Level answers

All answers ▸

Give the general solution of the second order ODE dy2/d2x - 4dy/dx + 3 = 0


Prove De Moivre's by induction for the positive integers


Given a curve with parametric equations, x=acos^3(t) and y=asin^3(t), find the length of the curve between points A and B, where t=0 and t=2pi respectively.


Split x^4/[(x^2+4)*(x-2)^2] into partial fractions and hence differentiate it