You know that if you could post using even basic LaTeX, we could understand what you are asking. It is very hard to know what you are asking.
(2) Show that lim_{x \to x_0} f(x) = L if and only if lim_{x \to 0} f(x+x_0) = L. Assume x_0 and L are finite.
(3) Show that if lim_{x \to x_0} f(x) = L and E is a set which has x_0 as an accumulation point, then lim_{x \to x_0, x in E} f(x) = L. Give an example to show that the converse may fail. Assume x_0 and L are finite.
can anyone solve any of these?