Do I have to get both $x\to2^+$ and $x\to2^-$? Then how can I get those limits? If $x\to2^+,x=2+h$ do I have to pull it in that formula? (ahh, I can't describe well ;( understand me I'm Korean) I can solve the question by drawing a graph, so please don't answer it. I really want to know how to solve it. And the answer is 6 (not 7).