Hi, I forget how to tell when a velocity graph is speeding up or slowing down.

Below is the image, where I have to put where it is speeding up/slowing down in interval notation.

I thought it was speeding up between (0,1) because it has positive slope there and slowing down from (1,3). Can someone correct my logic? Any help would be great, I've literally googled/looked at my textbook and both didnt help me.