Chapter 1: Problem 5
In exercises \(5-7,\) write the given term without using exponents. $$ \left(8 x_{1}-5 x_{2}+11\right)^{-1 / 3} $$
Short Answer
Expert verified
\(\frac{1}{\sqrt[3]{8x_1 - 5x_2 + 11}}\)
Step by step solution
01
Understand the Expression
The expression given is \((8x_1 - 5x_2 + 11)^{-1/3}\). This is an exponent expression, specifically a fractional exponent that indicates a root.
02
Identify the Meaning of the Exponent
The exponent \(-1/3\) means two things: the negative sign indicates taking the reciprocal of the expression, and the \(1/3\) indicates taking the cube root of the expression.
03
Write the Reciprocal
The negative exponent means we take the reciprocal of the expression \((8x_1 - 5x_2 + 11)\). This gives us \(\frac{1}{(8x_1 - 5x_2 + 11)^{1/3}}\).
04
Write as a Root
The exponent \(1/3\) after taking the reciprocal indicates a cube root. Therefore, \((8x_1 - 5x_2 + 11)^{1/3}\) is equivalent to \(\sqrt[3]{8x_1 - 5x_2 + 11}\).
05
Combine the Steps
Substitute the cube root back into the reciprocal expression. The final expression without exponents is \(\frac{1}{\sqrt[3]{8x_1 - 5x_2 + 11}}\).
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.
Understanding Exponents
Exponents are a shorthand way to express repeated multiplication of the same number. For example, the expression \( a^n \) represents multiplying \( a \) by itself \( n \) times. Exponents make it easier to work with very large or very small numbers, and they help simplify algebraic expressions.
There are different kinds of exponents:
There are different kinds of exponents:
- Positive whole number exponents indicate multiplying the base by itself the given number of times. For example, \( 2^3 = 2 \times 2 \times 2 = 8 \).
- Fractional exponents, like \( x^{1/2} \), are a way to indicate roots. For example, \( x^{1/2} \) is the same as \( \sqrt{x} \), which is the square root of \( x \).
- Negative exponents represent reciprocal values, such as \( x^{-1} = \frac{1}{x} \).
Exploring Cube Roots
Cube roots are special kinds of roots that mean finding a number which, when multiplied by itself three times, gives the original number.
The cube root of a number \( x \) is written as \( \sqrt[3]{x} \) or equivalently as \( x^{1/3} \).
The cube root of a number \( x \) is written as \( \sqrt[3]{x} \) or equivalently as \( x^{1/3} \).
- For instance, \( \sqrt[3]{8} = 2 \) because \( 2 \times 2 \times 2 = 8 \).
- Cube roots can be applied not only to numbers but also to algebraic expressions, similar to what we saw in the exercise, where \( (8x_1 - 5x_2 + 11)^{1/3} \) became \( \sqrt[3]{8x_1 - 5x_2 + 11} \).
The Role of Reciprocals
Reciprocals are mathematical expressions where the original number is flipped over one.
If you have a number \( a \), its reciprocal is \( \frac{1}{a} \). When applied to fractions, you simply invert the fraction; for example, the reciprocal of \( \frac{b}{c} \) is \( \frac{c}{b} \).
If you have a number \( a \), its reciprocal is \( \frac{1}{a} \). When applied to fractions, you simply invert the fraction; for example, the reciprocal of \( \frac{b}{c} \) is \( \frac{c}{b} \).
- Reciprocals are useful when dealing with negative exponents because they translate the problem into a form that's easier to work with. For example, \( a^{-1} \) becomes \( \frac{1}{a} \).
- In more complex expressions like the one in our exercise, the reciprocal helps to eliminate the negative exponent by placing the expression in the denominator. This results in a much more intuitive form, \( \frac{1}{\sqrt[3]{8x_1 - 5x_2 + 11}} \).