Solving sin(x)/sin(x+215) = ab/cd

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To solve the equation sin(x)/sin(x+215) = ab/cd, one can utilize the identity that relates sin(x) and sin(x+a). The equation can be simplified to the form sin(x)(1-bcos(a)) = bcos(x)sin(a). This leads to the expression tan(x) = bsin(a)/(1-bcos(a)), allowing for the use of the inverse tangent function to find x. The discussion highlights the transformation of the original equation into a solvable format. The approach effectively demonstrates how to manipulate trigonometric identities for problem-solving.
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This isn't homework, but I can't seem to access the math forum at the moment, so I thought I'd ask here.

Homework Statement


sin(x)/sin(x+215) = ab/cd.
Solve for x

Homework Equations


Is there any property for sin x / sin y so I can simplify this?
 
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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.
 
Thanks LCKurtz!
 
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