I am learning precalculus and my precalculus book gives this equation:
for this graph:
But when I enter that equation into some online graph tool like Symbolab ( https://www.symbolab.com/graphing-calculator ) I get this graph:
It seems that (many) online calculators cancel (x+1)(x-1) in numerator/denominator before drawing a graph.
So, which graph of those 2 is "correct"? Why?
P.S. My previous question was downvoted and removed as "not interesting for math community". That was very rude having in mind that I am beginner, looking for a help. Perhaps I should join some other forum for math beginners but I don't know which and where?