Use the figure to find the exact value of the trigonometric

Use the figure to find the exact value of the trigonometric function sin 2 theta. 41/841 -41/841 840/841 43/841

Solution

from the triangle: sin = 21/29

                     and cos = 20/29

we know that sin2 = 2*sin*cos

                                  = 2*(21/29)*(20/29) =0.9988 = 840/841