In this question The user seems to be new to the fundamentals of calculus. I tried to give the answer as concisely and on-point as possible. He had doubts regarding my answer so I tried to clear it by sending a link to the graph.
But how do I deal with users who tends to offer no regards too what the contributor is trying to explain and keep asking the same question again and again?
Yes I lost my temper and those CAPS (in the end) are clear signs to this. But I need some advice on how to deal with such users. Anyone?