Answer:
C. Robbie's glider
Step-by-step explanation:
P.S -The exact question is -
Given - Melissa and Robbie are flying remote control gliders.
The altitude of Melissa's glider, h(s), in feet, is modeled by this function, where sis time, in seconds, after launch.
m(s) = 0.4(s³ - 11s² + 31s – 1)
The altitude of Robbie's glider is modeled by function r, where sis time, in seconds, after launch.
To find - Which glider reaches the greater maximum altitude in the first 6 seconds after launch?
A. Neither glider reaches a maximum altitude on the given interval.
В. Melissa's glider
C. Robbie's glider
D. Both gliders reach the same altitude on the given interval.
Proof -
At t = 6 sec,
Melisa glider is
h(6) = 0.4((0.6)³ - 11(0.6)² + 31(0.6) – 1)
= 0.4( 0.216 - 3.96 + 18.6 - 1 )
= 0.4(13.856) = 5.5424
⇒h(6) = 5.5424
∴ we get
At t = 6 seconds, Melissa glider is at the altitude of 5.54 feet
Now,
From the figure, we can see that,
At t = 6 seconds, Robbie's glider is approximately at an altitude of 13 feet
Now,
As 13 > 5.5
So,
Robbie's glider is at maximum height in 6 seconds after the launch.
So,
The correct option is - C. Robbie's glider
