I've encountered a strange kinematics problem in a textbook.
Rest assured, I have long finished my studies in Physics, I simply decided to get back to the basics in order to refresh my skills.
The problem is the following:
"A particle is moving along the X-axis. The coordinate of the particle is changing with relation to time according to the law: $x = c_1t + c_2t^3$, where $c_1 = 2 m/s$, $c_2 = 1 m/s^3$.
a) The velocity and acceleration of the particle at a point of time = 2s
b) The mean velocity with which the particle travels in the first 3s"
The way I see it I can sort of unofficially take $c_2$ as the jerk, $c_1$ as the initial velocity and, maybe, the initial acceleration is = 0, even though nothing is mentioned about that. So the acceleration at 2s should be $2m/s^2$ and velocity should be $3m/s$ but the answer in the textbook is $v = 14m/s$ and $a = 12m/s^2$. I don't even want to talk about b).
I have no idea how this is supposed to be solved, one because I don't see any relevant information in the problem description and, two, because nothing like this was covered in the lesson of this problem.