What is the equation for solving for alpha?

[physics_dude]

i have this equation. While working on a problem i came across this. I need to solve for alpha. I can't seem to get anywere. I tried the problem two ways and end up havin the same problem so any help be appreciated. Thanks in advance

Solve for alpha

M/rF = Sin(alpha)Cos(theta) + Sin(theta)Cos(alpha)

(this is as far as i would get than get stuck
i no the value for M,r,F,theta. Need to find alpha
thanks a lot

 

[Tide]

$\sin (a+b) = \sin a \cos b + \cos a \sin b$

 

[physics_dude]

got it
thanks

 

[Pyrrhus]

Here's a wild idea

$$\arcsin(\frac{M}{rF}) = \theta + \alpha$$

Edit: Oh damn, just when i was typing it