# Help solving trigonometric equation?

1. Aug 8, 2008

### hyper

Can someone please give me some tips on how to solve this? :

400*(2,2*cosV-1)*tanV=20*9,81, I am supposed to find V, but I can't see how to solve this equation.

2. Aug 8, 2008

### snipez90

Does 2,2 represent 2.2 and 9,81 9.81? Show how much you've done already.

3. Aug 8, 2008

### hyper

Yes, i am sorry, I am not familiar with the correct way to write decimals.

What I have done allready? I made this equation from a statics problem which required equlibrium of a disk with a spring around a quarter circle. I have tried checking the equation numerically and it gives the right answers, but I have no idea how I am supposed to solve the equation mathematically.

4. Aug 8, 2008

### snipez90

It's ok I've seen them written that way. The main difficulty I'm having is dealing with these not so nice numbers. I figured I would write everything in terms of sin and cos which would bring me to 2.2sin(V)cos(V) = sin(V) + (9.81/20)cos(V). The left hand side is 1.1sin(2V) but I'm not certain about the right hand side.

I'm not sure if there are better manipulations but if not a numerical solution will have to do.