Respuesta :
Answer:
(a)t=10.5 seconds
(b)1764 feet
(c)t=21 seconds
Step-by-step explanation:
The equation of the projectile is given by:
[tex]H= -16t^2 + 336t[/tex]
(1)The ash projectile reaches its maximum height when the slope of the line is equal to zero.
First, we find the derivative of H.
[tex]H^{'}= -32t + 336[/tex]
When [tex]H^{'}=0[/tex]
[tex]= -32t + 336=0\\-32t=-336\\[/tex]
Divide both sides by -32
t= 10.5 seconds
(2) The maximum height occurs at the point where t= 10.5
[tex]H= -16t^2 + 336t\\H= -16(10.5)^2 + 336(10.5)\\Max(H)=1764 feet[/tex]
(3)The ash projectile returns back to the ground when its Height, H =0
[tex]H= -16t^2 + 336t\\\\-16t^2 + 336t=0\\-16t^2 =- 336t\\-16t=-336\\t=21 seconds[/tex]
The ash projectile returns to the ground after 21 seconds.