Use One Function to Solve for Another Function
Sometimes you have to solve for a trigonometry function in terms of another function. For example, you may be given the cosine of an angle, and from that, you need to determine the sine and tangent of that angle.
Identify the sides given by the cosine function.
measures 12 units, and the hypotenuse measures 13 units.
Find the measures of the missing side.
Using the Pythagorean theorem, you find that the missing side (the opposite side) measures 5 units.
Determine the values of the sine and tangent.