Answer:
Step-by-step explanation:
Let maximum height be H (at time t = 0.69 s)
then the height at time t can be written as
f(t) = H - c(t - 0.69)² (c is a constant)
at t = 0, f(0) = 70, so
H - c(0 - 0.69)² = 70
H - c(0.69)² = 70 (1)
at t = 2.75 s, f(t) = 0, so
H - c(2.75 - 0.69)² = 0
or H - c(2.06)² = 0 (2)
(1) - (2):
c(2.06² - 0.69²) = 70
c = 70/(2.06² - 0.69²) = 18.58
From (2)
H = 18.58(2.06)² = 78.85
Then
f(t) = 78.85 - 18.58(t - 0.69)²
