SOLUTION: Please help me to prove using de Moivre's Theorem that {{{ 4*sin^3 (x) =3*sin(x) -sin(3*x)}}}

SOLUTION: Please help me to prove using de Moivre's Theorem that {{{ 4sin^3 (x) =3sin(x) -sin(3*x)}}}

Question 1034445: Please help me to prove using de Moivre's Theorem that
Answer by robertb(5830) (Show Source): You can put this solution on YOUR website!
,after applying de Moivre's and direct expansion.
= .
Now equate the imaginary parts of the first complex quantity and the last complex quantity.
==>
==>
==> , or .
As an added bonus, what would happen if you equated the real parts of the first complex quantity and the last complex quantity? Try it out yourself.

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