Numerically and graphically determine a $\delta$ corresponding to $(a) \varepsilon=0.1$ and $(b) \varepsilon=0.05 .$ Graph the function in the $\varepsilon-\delta$ window $[x$ -range is $(a-\delta, a+\delta)$ and $y$ -range is $(L-\varepsilon, L+\varepsilon)]$ to verify that your choice works.
$$
\lim _{x \rightarrow 0}\left(x^{2}+1\right)=1
$$