Help verifying this ID?

**generalmeow** · March 23rd 2011, 09:18 AM

sin³(3x) = ½(sin(3x))(1-cos(6x))

I'm just stumped...everything I've tried has turned into a complete mess. Thanks a bunch for any ideas!

**TheEmptySet** · March 23rd 2011, 09:20 AM

Originally Posted by generalmeow

sin³(3x) = ½(sin(3x))(1-cos(6x))

I'm just stumped...everything I've tried has turned into a complete mess. Thanks a bunch for any ideas!

$\displaystyle \sin^3(3x)=\sin(3x)\sin^2(3x)=\sin(3x)\left[\frac{1}{2}(1-\cos(6x))\right]$

**Chris L T521** · March 23rd 2011, 09:21 AM

Originally Posted by generalmeow

sin³(3x) = ½(sin(3x))(1-cos(6x))

I'm just stumped...everything I've tried has turned into a complete mess. Thanks a bunch for any ideas!

For this one, show that RHS implies LHS.

For a hint, reference the spoiler.

Spoiler:

EDIT: TES beat me!

Thread: Help verifying this ID?