Chapter 9.1, Problem 91E

To determine

(a)

To find:

The third partial sum of the given series ${\displaystyle \sum _{n=1}^{\infty }4{\left(-\frac{1}{2}\right)}^n}$.

To determine

(b)

To find:

The fourth partial sum of the given series ${\displaystyle \sum _{n=1}^{\infty }4{\left(-\frac{1}{2}\right)}^n}$.

To determine

(c)

To find:

The fifth partial sum of the given series ${\displaystyle \sum _{n=1}^{\infty }4{\left(-\frac{1}{2}\right)}^n}$.