The first part is straightforward, just plug in x = 1. For the second part, what is meant by compare? Are you asked to show which one converges faster per the number of terms?
Btw, the Wallis product for pi is
[Math]\displaystyle \prod_{n=1}^{\infty} \frac{2n}{2n-1} \cdot \frac{2n}{2n+1} = \frac{2}{1} \cdot \frac{2}{3} \cdot \frac{4}{3} \cdot \frac{4}{5} \cdot \frac{6}{5} \cdot \frac{6}{7} \cdot \frac{8}{7} \cdot \frac{8}{9} \cdots = \frac{\pi}{2}[/tex]
The Leibnitz series is...
(1)
... so that after 2n iterations the last summed term is ...
The Wallis product [in logarithmic version...] is...
(2)
... so that after 2n iterations the last summed term is ...
The two methods seem to be comparable in speed: both are very slow ...
Kind regards