# Thread: Rate of Change

1. ## Rate of Change

Hey, I'm doing some homework and I didn't understand this problem. It's a little confusing.

Find $\displaystyle x_0$ given that the rate of change of $\displaystyle y=2(x^2) + x -1$ with respect to x at x= $\displaystyle x_0$ is 4

The first thing I did was integrate the function. But I'm not sure what to do next.

2. Originally Posted by discobob
Hey, I'm doing some homework and I didn't understand this problem. It's a little confusing.

Find $\displaystyle x_0$ given that the rate of change of $\displaystyle y=2(x^2) + x -1$ with respect to x at x= $\displaystyle x_0$ is 4

The first thing I did was integrate the function. But I'm not sure what to do next.
They have told you (a bit ambiguously I might add) that $\displaystyle y'=4$ at $\displaystyle x=x_0$. So find $\displaystyle x_0$

3. wow, that's it? It was written a bit confusingly. Thank you very much for the help.

4. Originally Posted by discobob
wow, that's it? It was written a bit confusingly. Thank you very much for the help.
So, what do you have for $\displaystyle x_0$?