If 3sin(x + pi/3) = 2cos(x - 2pi/3), find tanx?

I started doing it using the sum and difference formulas but didn't end up getting the correct answer. Could someone show me how to do it using the sum and difference formulas?

Thanks in advance.

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- Jul 18th 2010, 03:05 AMD7236Trigonometric equation?
If 3sin(x + pi/3) = 2cos(x - 2pi/3), find tanx?

I started doing it using the sum and difference formulas but didn't end up getting the correct answer. Could someone show me how to do it using the sum and difference formulas?

Thanks in advance. - Jul 18th 2010, 03:15 AMundefined
- Jul 18th 2010, 03:23 AMProve It
You should know

and

.

So in your case

. - Jul 18th 2010, 03:34 AMProve It
- Jul 18th 2010, 03:46 AMundefined
Since Prove It posted a full solution, here's another way.

Use

if you know it, otherwise use sin and cos angle sum like Prove It.

Here

I was busy typing and didn't see your recent post until just now. I think your way is a bit easier than mine, anyway.