Think about we have a infinite series
summation (j from 0 to infinity) (0.5)^2j=4/3
How did we get this answer?Please help me.
I can't get line breaks to parse properly on this forum...
There are several ways to do both questions. Here's just an example
View the first one as a geometric series of a geometric series
the second is a little tricker...
Let's try to find a general form for assuming |x| is less than 1
there are probably much easier ways to do this