Chapter 7.9, Problem 33WE

To determine

To explain: The expression $b^{-1}$ is not defined when $b=0$ .

Answer to Problem 33WE

Fraction of the form $\frac{p}{q}$ are defined when $q\ne 0$ where p and q are real numbers.

Explanation of Solution

Given information:

The expression $b^{-1}$ .

Formula used:

The expression $a^{-n}$ is expressed as $\frac{1}{a^n}$ where a is a nonzero real number and n is a positive integer.

Calculation:

Consider the expression $b^{-1}$ .

Recall that expression $a^{-n}$ is expressed as $\frac{1}{a^n}$ where a is a nonzero real number and n is a positive integer.

Apply it,

  $\begin{array}{c}{b}^{-1}=\frac{1}{b^1}\\ =\frac{1}{b}\end{array}$

Fraction of the form $\frac{p}{q}$ are defined when $q\ne 0$ where p and q are real numbers.

Therefore, the expression $\frac{1}{b}$ is defined only when $b\ne 0$ .