I have a content related query. Please go to this link first : https://www.teachoo.com/3741/706/Misc-21---Does-there-exist-a-function-which-is-continuous-but-not/category/Miscellaneous/ Now, see case-5 --> LHD --> Third line. There should be lim h->0 [ (-2(0)+1) - (-2(-h) +1) ] / h Because the function is "-2x +1" for x ≤ 0. Please tell me if I'm correct or not. My intention is not to tell that you have done a mistake. I just want to know the reason for it if it is correct. Please reply