Chapter 1, Problem 7PE

(Approximate $\pi$ ) $\pi$ can be computed using the following formula:

$\pi =4\times \left(1-\frac{1}{3}+\frac{1}{5}-\frac{1}{7}+\frac{1}{9}-\frac{1}{11}+\mathrm{...}\right)$

Write a program that display the result of $4\times \left(1-\frac{1}{3}+\frac{1}{5}-\frac{1}{7}+\frac{1}{9}-\frac{1}{11}\right)$ and $4\times \left(1-\frac{1}{3}+\frac{1}{5}-\frac{1}{7}+\frac{1}{9}-\frac{1}{11}+\frac{1}{13}\right).$ Use 1.0 instead of 1 in your program.