Let alpha and beta be angles such that P is the terminal point for alpha and Q is the terminal point for beta.
Say that cos(alpha) = 12/13 and cos(beta) = -4/5
Then, if R = (r_1, r_2), and S = (s_1, s_2), enter r_1, r_2, s_1, and s_2.
b) If T = (t_1, t_2), and U = u_1, u_2), enter t_1, t_2, u_1 and u_2
Please show steps. :)