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Exercises Expressions, exponents and radicals

Example 7.35 from Prealgebra, 7.4 Properties of Identity, Inverses, and Zero

Properties of Identity, Inverses, and Zero: example 7.35

Find the multiplicative inverse: ⓐ $9$ ⓑ $- \frac{1}{9}$ ⓒ $0.9$ .

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

1
Solution
To find the multiplicative inverse, we find the reciprocal.
1. ⓐ The multiplicative inverse of $9$ is its reciprocal, $\frac{1}{9} .$
2. ⓑ The multiplicative inverse of $- \frac{1}{9}$ is its reciprocal, $−9 .$
3. ⓒ To find the multiplicative inverse of $0.9,$ we first convert $0.9$ to a fraction, $\frac{9}{10} .$ Then we find the reciprocal, $\frac{10}{9} .$

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

Find the multiplicative inverse: ⓐ $5$ ⓑ $- \frac{1}{7}$ ⓒ $0.3$ .

How did it go?

PreviousProperties of Identity, Inverses, and Zero: example 7.34 Next Properties of Identity, Inverses, and Zero: example 7.36

From Prealgebra (1st edition) by OpenStax (Rice University), section 7.4, licensed under CC BY 4.0. Original at openstax.org. We split the solution into steps; the words, numbers and figures are the book's. OpenStax doesn't endorse this site.