Combine the following expressions into a single sinusoid and plot both the combined and original expressions in Matlab across 2 periods. a) 2cos(3t)-cos(3t-pi/4) b) sin(2t- pi/4) + 2cos(2t-pi/3) c) cos(t) - sin(t) d) 10cos((pi*t) + pi/3) + 8cos((pi*t)-pi/3)) Include hand calculations showing how single sinusoid was obtained along with Matlab code.