Heres another equation I have come up with that I would like to solve:

Where k1,k2,k3,k4,k5,k6 are constants and would like to solve for theta.

Im trying to solve this so that I can use it in a program I am making, it is generated from a set of equations im trying to solve which can be solved using the quartic euqation but I would prefer a solution which involves less operators used .

Thanks again.