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# trgi questions.. i dont know what to do watch

1. 1) find values for 0-360 for which:
7cosx+sinx=5
I though about using the RCosx, Rsinx but didnt get the right answer,
2) solve for 0-360
2cos(x+50)=sin(x+40)
Im thinking i should use addition formulaes but then didnt know what to do.
3) solve for 0-pi
3sinx+sinx=sin2x
do i used sin2x=2sinAcosB here? then how do i get just sin?
4) sinx=cos^2x for 0-360
i just dont seem to be able to do trig anymore!
xxxx
2. Rcos(x-a)=Rcosxcosa + Rsinxsina
Rcosx+7
Rsinx+1
tanx= 1/7
x=tan^-1=8.13
R^2=1+7^2
R= square root of 50
Hopefully you can solve x from here

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Updated: January 18, 2010
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