Part 2: Verifying and proving trig identities Using Graphs: By denition, to verify is to present evidence, such as a graph. Consider the rst of the three Pythagorean identities. sin29 + c0529 = l. The following is a graph of the left side of this equation (the function x) = sin29 + c0529). To verify that a trig statement is an identity. using graphing, assumes that the functions are dened for all values of x within the interval being considered. 2 -3. l4 1_5'_'.-' 1.57 3.14 3. Now describe what the graph of the right side of the equation (fix) = 1] would look like. Compare it to the previous graph