Question

A projectile is thrown upward so that its distance above the ground after t seconds is h = - 16t2 + 440t.

After how many seconds does it reach its maximum height?

Answer 1

few ways to solve this

Answer 2

are you familiar with derivatives?

Answer 3

with a graph correct?

Answer 4

Without Calculus you know that this graph will look like this

Answer 5

oh ok

Answer 6

so you know it hits its maximum height at its' vertex.

you know how to find the x for the vertex by

\[x=\frac{-b}{2a}\]

Answer 7

x so happens to be time in our case =P

Answer 8

ohhhh