Chapter 5: Problem 103
Simplify each expression. a) \(\left(\frac{4}{9}\right)^{-3}\) (b) \(\left(-\frac{u}{v}\right)^{-5}\)
Short Answer
Expert verified
(a) \(\frac{729}{64}\), (b) \(-\frac{v^5}{u^5}\)
Step by step solution
01
Understand Negative Exponents
A negative exponent means you take the reciprocal of the base and then apply the positive exponent. For example, \(a^{-b} = \frac{1}{a^b}\).
02
Simplify (a) \(\left(\frac{4}{9}\right)^{-3}\)
Applying the rule of negative exponents, we get: \(\left(\frac{4}{9}\right)^{-3} = \left(\frac{9}{4}\right)^3\).
03
Calculate \(\left(\frac{9}{4}\right)^3\)
Raise both the numerator and the denominator to the power of 3: \(\left(\frac{9}{4}\right)^3 = \frac{9^3}{4^3} = \frac{729}{64}\).
04
Simplify (b) \(\left(-\frac{u}{v}\right)^{-5}\)
Again, apply the rule of negative exponents: \(\left(-\frac{u}{v}\right)^{-5} = \left(-\frac{v}{u}\right)^5\).
05
Calculate \(\left(-\frac{v}{u}\right)^5\)
Raise both the negative fraction and its components to the power of 5: \(\left(-\frac{v}{u}\right)^5 = -\frac{v^5}{u^5}\).
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Positive Exponents
Positive exponents indicate how many times a number (the base) is multiplied by itself. For example, in the expression \(a^b\), the base \(a\) is multiplied by itself \(b\) times.
- Example: \(2^3 = 2 \times 2 \times 2 = 8\).
- Example: \(5^2 = 5 \times 5 = 25\).
Reciprocals
Reciprocals are closely related to both positive and negative exponents. The reciprocal of a number is 1 divided by that number. If you have a fraction, its reciprocal is switching the numerator and denominator.
- Example: The reciprocal of \(a\) is \(\frac{1}{a}\).
- Example: The reciprocal of \(\frac{3}{4}\) is \(\frac{4}{3}\).
Fractional Exponents
Fractional exponents represent roots. The numerator of the fraction is the power, and the denominator is the root. For instance, \(a^{\frac{1}{2}}\) represents the square root of \(a\), and \(a^{\frac{1}{3}}\) represents the cube root of \(a\).
- Example: \(4^{\frac{1}{2}} = \sqrt{4} = 2\).
- Example: \(8^{\frac{1}{3}} = \sqrt[3]{8} = 2\).
Negative Fractions
Negative fractions follow the same rules as positive fractions but with an added twist because of the negative sign. When a fraction has a negative exponent, we first take the reciprocal, making it easier to manage.
- Example: \(\left(\frac{4}{9}\right)^{-3}\) simplifies as follows: Take the reciprocal to get \(\left(\frac{9}{4}\right)^3\) and then calculate to get \(\frac{729}{64}\).
- Example: \(\left(-\frac{u}{v}\right)^{-5}\) converts first to \(\left(-\frac{v}{u}\right)^5\) and then calculates as \(-\frac{v^5}{u^5}\).