we are asked to evaluate the value of sin 2 theta, cos 2 theta and tan 2 theta where theta is a 2nd quadrant angle and the expression sin theta = 3/5 is valid. In this case, theta is equal to 143.13 degrees. hence sin2 theta is equal to -0.96; cos 2 theta is equal to 0.28 and tan 2 theta is equal to -3.4286
