Physics - mechanics?

Question

I'm new to the physics course, and these examples are in my text book, but the answers are not given, I'm pretty lost!


An object moves along the x-axis according to x(t) = (300t² - 2.00t + 3.00)m
Determine:
(a) the average speed between t =2.00 s and t = 3.00 s,

(b) the instantaneous speed at t = 2.00 s and t = 3.00 s,

(c) the average acceleration between t = 2.00 s and t = 3.00 s

(d) the instantaneous acceleration at t = 2.00 s
and t = 3.00 s.

Thanks in advance!

Answer 1

a) velocity is d(x(t)/dt or
(do you have the problem stated correctly? Should it be 3.00t^2? I will assume yes)
6.00t-2.00
Since this is straight line, the value at t=2 is 10, and the value at t=3 is 16, the average is 13

b is answered above 10 and 16

c,d acceleration is dv(t)/dt or
6.00, which is a constant, so average and instantaneous are always the same.

j