Respuesta :
Answer:
20 seconds
Step-by-step explanation:
h(t) = -16t2 + 640t
to find the maximum value =>
h'(t) = 0
-32t + 640 = 0
-32(t -20)= 0
t-20 = 0
t = 20 seconds
Find derivative of h(t)
[tex]\\ \rm\longmapsto \dfrac{d}{dx}(-16t^2+640t)[/tex]
[tex]\boxed{\sf \dfrac{d(x^n)}{dx}=nx^{n-1}}[/tex]
[tex]\\ \rm\longmapsto -32t+640[/tex]
- Now its be 0
[tex]\\ \rm\longmapsto -32t+640=0[/tex]
[tex]\\ \rm\longmapsto -32t=-640[/tex]
[tex]\\ \rm\longmapsto t=\dfrac{-640}{-32}[/tex]
[tex]\\ \rm\longmapsto t=20s[/tex]