##### Trigonometry Workbook For Dummies The trigonometry equations that require finding a greatest common factor, factoring it out, and then solving the equation could look like one of the following two equations: Both of these equations are solved here. 1. Factor out sin x from each of the two terms. 2. Set the two different factors equal to 0. 3. Solve for the values of x that satisfy both equations. Use a scientific calculator. All these values are solutions for the original equation. The complete list is x = 0°, 60°, 180°, 300°. 4. Move the term on the right to the left by subtracting it from each side. A common error in algebra — which could carry over in trig — is to divide each side by the common factor. You should never do that, because you’ll lose part of the solution.

1. Factor out the cos x from each term. You don’t want to divide each side by cos x, because you’ll lose a solution if you do.

2. Set the two different factors equal to 0. 3. Solve for the values of x that satisfy both equations. So the solutions are all of the form x = 90° + 180°n or x = 60° + 180°n.