Answer:
The maximum value of f(t) is 576, the maximum height of the firework.
Step-by-step explanation:
h = -16t² + v₀t + h₀
Data:
v₀ = 192 ft/s
h₀ = 0
Calculation:
h = -16t² + 192t
This is the equation of a parabola.
We must solve the equation to find the maximum height.
The coefficient of t² is negative, so the parabola opens downward, and the vertex is a maximum.
Complete the square
(a) Divide both sides by -16 to make the coefficient of t² equal to 1.
(-1/16)h = t² - 12t
(b) Square half the coefficient of t
(-12/2)² = (-6)² = 36
(c) Add and subtract it on the right-hand side
(-1/16)h = t² - 12t + 36 - 36
(d) Write the first three terms as the square of a binomial
(-1/16)h = (t - 6)² - 36
(e) Multiply both sides by -16
h = -16(t - 6)² + 576
You have converted your equation to the vertex form of a parabola:
y = a(t - h)² + k = 0,
where (h, k) is the vertex.
h = 6 and k = 576, so the vertex is at (6, 576).
The vertex represents the maximum height of the firework.
The Figure below shows that your firework reaches a maximum height of 576 ft 6 s after ignition.