Problema Solution
Brittany is jumping on a trampoline. After 4 jumps, she jumps up with an initial velocity of 17 feet per second. The fuction d(t)=17t-16t^2 gives the height in feet of Brittany above the trampoline as a function of time in seconds after the fifth jump. How long after her fifth jump will it take for her to return to the trampoline again?
Answer provided by our tutors
in order to return to the trampoline again, d(t) must be zero
hence,
d(t) = 0
<=> 17t - 16t^2 = 0
<=> t(17 - 16t) = 0
(assuming t is not 0)
=> 17 - 16t = 0
<=> t = 17/16 or t = 1.0625
answer: 1.0625 seconds after 5th jump