Proving Convergence: Showing That x_n and y_n Have the Same Limit

cragar
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Homework Statement


Show that if x_n is a convergent sequence, then the sequence given by that average values also converges to the same limit.
y_n=\frac{x_1+x_2+x_3+...x_n}{n}

The Attempt at a Solution


Should I say that x_n converges to some number P. so now I need to show that
y_n converges to P as well.
Do I need to show that y_n-P< \epsilon
 
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That's exactly what you need to show. Got any ideas?
 
so x_n is my nth term right, and also what the limit converges to.
So x_n=P
So I should have(x_1+x_2+x_3+...P)=Pn maybe I can work on manipulating the sum and see if certain parts are less than other parts.
 
Let me give you a hint:

Define the limit of x_n to be L then there is (for every epsilon>0) a N such that for n > N

|x_n-L|< \epsilon

Now we get:

\left| \frac{x_1+x_2+x_3+...+x_n}{n} -\frac{nL}{n} \right| = \frac{|x_1-L| +|x_2-L| +...+|x_n-L|}{n} =\frac{|x_1-L| +|x_2-L| +...+|x_N-L| + |x_{N+1}-L|+...+|x_n-L|} {n} < \frac{|x_1-L| +|x_2-L| +...+|x_N-L|}{n} + \frac{(n-N)}{n} \epsilon < ...

Can you fill in the dots at the end?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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