1. ## Horrible tan equation

$3960\,\arctan \left( {\frac {2255}{12}}\,{\frac {1}{\sqrt {-13530\,c}}
} \right) {\frac {1}{\sqrt {-13530\,c}}}=17
$

Assuming c is negative.

Okay, I've been working on this for some time now. The equation is part of a bigger problem. I just need a value for c. I know it's about -2.5 by using a numerical method. Does anyone see how this could be solved algebraically?

Thanks

2. Originally Posted by sam45
Does anyone see how this could be solved algebraically?

Thanks
Not I, numerical method it is.