Hi Jasmina8.

Substitution is the easiest way to find limits, so that's good. Substitution means that you simply substitute the value x approaches for x in your function/expression and see what value you get. For a lot of basic expressions, this value is the limit you want to find.

What do you get when you plug in -1/2 for x in the 1st problem? How about 0 in the second?