Which expression is equivalent to 3cos2(StartFraction theta Over 2 EndFraction) minus 3?

Three-halves(cos(ϴ) – 1)
Three-halves(cos(ϴ) – 5)
3(cos(ϴ) + 2)
3(cos(ϴ) + 1)

Which expression is equivalent to 3cos2StartFraction theta Over 2 EndFraction minus 3 Threehalvescosϴ 1 Threehalvescosϴ 5 3cosϴ 2 3cosϴ 1 class=