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# C3 - Ex 7A watch

1. Im hopeless at solving the equations with for e.g
' 3cosx = 2sin(x + 60)' in 0 <x< 360.
any help rearranging this to get my values before the A-S-T-C quadrants, thanks.
2. 3cosx = 2sinxcos60 + 2cosxsin60 [expand]
3cosx = sinx + sqrt(3)cosx [use values of sin60, cos60]
(3-sqrt3)cosx = sinx
tanx = 3-sqrt3
3. thanks,
expanded it right, just dumb when it comes to using the 30,60's
4. same type but with 2 sin's

ive expanded to get :
sinxcos30 + cosxsin30 + 2 sinx = 0

so sinx (sqrt3/2) + cosx(1/2) + 2sinx = 0
then cannot get right values ?

then the values are 170.1 and 350.1, probably something simple.
5. Divide through by sinx, move all constants to one side, manipulate to get tanx =

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Updated: October 16, 2006
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