Don't let him hinder your learning if that's what is happening.

But I just want to say, those annoying stupid questions are why he's going to do better. He's figuring out how the math works. HOW it works. He's not memorizing anything. Memorizing is terrible for learning. You will forget that stuff as soon as you get out of the class.

That said you also can find his laziness and general attitude unattractive, and it sure won't be a positive in the future. Employers can probably find someone just as smart who is also trying. Or someone who is trying so hard they blow past him.

Also, he can easily study by himself and probably just wants to do it with you. But like I said, if it's hurting you, don't. Tell him and he should be fine with it. If you tell him it's making you do worse even though he wants to that is bad.