What's C going to be? If we just look at this part of the equation, just this equation right over here, if you subtract 3 from both sides, you get C is equal to negative 6. Now we know the exact expression that defines velocity as a function of time. V of T is equal to T, T plus negative 6, or T minus 6. We can verify that. The derivative of this with respect to time is just 1, and when time is equal to 3, 3 minus 6 is indeed negative 3. We've been able to figure out velocity as a function of time.