If cosA=3/4, then the value of 16cos2(A/2)−32sin(A/2)sin(5A/2) is
-4
-3
3
4
The given expression is equal to
8(1+cosA)−16(cos2A−cos3A)=8(1+cosA)−162cos2A−1−cosA4cos2A−3=81+34−162×916−1−344×916−3=14−(18−16−27+36)=3.