Problem:

1. Given the sequence $\displaystyle x_n(s) = (|s|+\frac{1}{n})^{-1/3}$ and function $\displaystyle x(s)=|s|^{-1/3}$. show that $\displaystyle x_n\rightarrow x$

in $\displaystyle L_2(-1,1)$

2. How can we use this to deduce that $\displaystyle C[-1,1]$ (with the max norm) is not complete.

Pathetic Attempt:

1. $\displaystyle lim_{n\rightarrow \infty}||x_n(s)-x(s)||_{L_2} = lim_{n\rightarrow \infty} \int^1_{-1} |x_n(s)-x(s)|^2 = 0$

because $\displaystyle lim_{n\rightarrow \infty} 1/n = 0$.

2. The limit $\displaystyle x(s)$ isn't in C[-1,1] so its not complete...

Very bad I know.

Any suggestions are welcome.