Hi chemic_23, well you haven't really asked a question. In answer to you how do you square [itex]cos\beta[/itex] (i assume that's what you meant) you can square it like any other number as [itex]\textbf{cos\beta}[/itex] will be a real number if beta is a real number. Is you question find the solutions to this equation, because there are an infinite number of them?
If you could clarify you question then I am sure you'll find the help you need :D