The acceleration of the position function s(t) = 4t^2– 8t + 2 when t = 7.

a) 7
b) 48
c) 142
d) 8

3 answers

s(t) = 4t^2– 8t + 2 when t = 7
= 4(7)^2-8(7)+2
= 4(49)-56+2
= 196-54
s(t) = 4t^2– 8t + 2 when t = 7
= 4(7)^2-8(7)+2
= 4(49)-56+2
= 196-54
= 140+2
= 142
acceleration is the 2nd derivative of s(t)

s(t) = 4t^2– 8t + 2
v(t) = 8t - 8
a(t) = 8

since the acceleration is constant,
when t = 7, a = 8 units of distance/(units of time)^2