How do I simply this (there should be a trig. identity involved

[Linus Pauling]

1. This was actually a center of mass problem, so I got the equation below:



2.[T_2*sin(theta2)] / [T_1*sin(theta1) + T_2*sin(theta2)]



3. This is part of a solution I obtained for a physics problem. I know there is some trick with a trig indentity that I can use to simplify this. What is the identity?

 

[Linus Pauling]

Here's a visual aid: