Help on a De Moirvre's Question (1 Viewer)

[BlakPat]

Hello everyone
Mispelt De Moivre's- sorry
Just got stuck on a question.
Could i have a bit of assistance for this one :/
Thanks =)

 

[Carrotsticks]

Split the angles into half angles.

so cosX = 2cos^2(x/2) - 1 and sinX= 2sin(X/2)cos(X/2).

 

[bobmcbob365]

first thing that comes to mind is that there is a change from theta on the LHS to theta/2 on the RHS
so u could try using double angle formula.
and heyyyy, tht means you can get rid of the 1's in both brackets.
and then de moivre's from then on

 

[BlakPat]

Thanks for all your help, jono and henderson =)