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tony873004
Jun16-11, 07:21 PM
This isn't homework, but I can't seem to access the math forum at the moment, so I thought I'd ask here.

1. The problem statement, all variables and given/known data
sin(x)/sin(x+215) = ab/cd.
Solve for x

2. Relevant equations
Is there any property for sin x / sin y so I can simplify this?

LCKurtz
Jun16-11, 10:19 PM
Your equation has the form sin(x) = bsin(x+a) = bsin(x)cos(a) + bcos(x)sin(a)
= bsin(x)(cos(a) + bsin(a))

sin(x)(1-bcos(a)) = bcos(x)sin(a)
\frac{\sin(x)}{\cos(x)}=\tan(x)=\frac{b\sin(a)}{1-b\cos(a)}

You can now solve using the inverse tangent function.

tony873004
Jun17-11, 02:34 PM
Thanks LCKurtz!