How Do You Calculate Velocity from a Position-Time Equation?

[chound]

The position of an object moving along x-axis is given by x=a+b(t*t) where a =8.5m, b=2.5m/(s*s) and t is time. What is the velocity at t=2s? I think differential calculus should be used

 

[whozum]

If that x equation is x = a+bt^2, then just differentiate wrt to time to get velocity.

 

[futb0l]

Yupp, just get dx/dt and then make t = 2.

 

[chound]

Is it this:
dx/dt = d(a+bt^2)/dt
After this what should I do?

 

[James R]

Do you know how to differentiate?

If y = a + bx^2, what is dy/dx?

You have x = a + bt^2, and you know v=dx/dt, so what is v(t)?