Limits Question

[ciluvmathf]

hi, good evening. how would i go about doing part (ii). why is there a plus sign and a minus sign?

 

[tkhunny]

The cute little plus or minus signifies a one-sided limit.

1⁺ suggests sneaking up on 1 from numbers that are greater than 1. (Sometimes called "the right" or the "positive side") and ignoring, for the moment, that there are any numbers less than 1.

Can you guess what 1^- means?

 

[HallsofIvy]

For \(\displaystyle \lim_{x\to 1^+} f(x)\) ignore the definition of f(x) for x< 1.
What is \(\displaystyle \lim_{x\to 1} 3- x\)?

For \(\displaystyle \lim_{x\to 1^-} f(x)\) ignore the definition of f(x) for x> 1.
What is \(\displaystyle \lim_{x\to 1} 1+ x\)?