sin2x+sin4x=0,9696+2cos3xsinx

How much is x ?

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- Mar 14th 2006, 05:34 AMtotalnewbieTrigonometry
sin2x+sin4x=0,9696+2cos3xsinx

How much is x ? - Mar 14th 2006, 08:26 AMTD!
I don't think you won't be able to solve this algebraicly, try a numerical approximation using a computer or (graphical) calculator.

- Mar 14th 2006, 08:50 AMCaptainBlackQuote:

Originally Posted by**TD!**

but since the next stage is to look up an inverse trig function the effort

of simplifying is probably not worth it and one might as well go straight

for a numerical solution.

The first solution is

The only advantage of simplifiing is that it will give you all of the solutions.

RonL - Mar 14th 2006, 10:52 AMThePerfectHackerQuote:

Originally Posted by**totalnewbie**

Thus,

Thus,

Thus,

Recognzing this sum formula for sine we have,

(As CaptainBlack said)

Thus,

Thus,

Which can be written more elegantly as,

Q.E.D.