I would never have solved it if I knew this fight were to happen. Okay, so x implying y aside, the tangent lines must be the same for it to be continuos. This is because of the fact that as you approach from the right, eg the Ax2+Bx equation, we say the slope of the line is heading toward N. From the left, eg the 3-x equation, we say the slope of the line is heading toward M. So, for continuity, I'm sure that you would all agree that the two lines had to be connected at the point (1,2), since it was at x=1 and 3-x=2.
Okay, so I lied about the whole x not implying y thing. If it is differentiable, then it implies it is continuous. And yeah, the quiz was worded wrong I do believe. It should be differentiable not continuos. Either way, It doesn't matter. You are correct if it does not need to be differentiable. But, to make sure it is absolutely continuous, and getting exact answers, you should see if it is differentiable.
Wow, I just check recent-posts. This is gonna be ninja'd.
