Question

A projectile is thrown upward so that its distance above the ground after t seconds is given by the function h(t) = -16t2 + 640t. After how many seconds does the projectile take to reach its maximum height? Show your work for full credit.

Answer 1

It would only be 1 second.

h(1)=−16(1^2)+(640)(1)

After simplification, the answer would be h = 624.

If you substituted 2 for t, you would see that h would get smaller. Each time you increased t, h would get smaller.