solve and put in a trig equation

Question

25 cos(2t)+12 sin(t+π/2)+2 cos^2(t)

Answer 1

25 Cos 2t +12 Sin (t+pi/2) + 2 Cos² t

= 25 Cos² t - 25 Sin² t  + 12 Cos t + 2 Cos² t 

= 27 Cos ² t  -25 Sin² t + 12 Cos  t

= 52 Cos² t -25 + 12 Cos t