Chapter 9: Problem 64
Rationalize each denominator. $$ \frac{2}{\sqrt[3]{a}} $$
Short Answer
Expert verified
The rationalized expression is \( \frac{2 \sqrt[3]{a^2}}{a} \).
Step by step solution
01
Identify the Problem
The problem asks to rationalize the denominator of the expression \( \frac{2}{\sqrt[3]{a}} \). Currently, the denominator is not a rational number because it contains a cube root.
02
Multiply by the Conjugate Fraction
To rationalize the denominator which is \( \sqrt[3]{a} \), we multiply both the numerator and the denominator by \( \sqrt[3]{a^2} \). This is because \( \sqrt[3]{a} \times \sqrt[3]{a^2} = \sqrt[3]{a^3} = a \), which is a rational number.
03
Apply the Multiplication
We perform the multiplication, resulting in: \[\frac{2 \times \sqrt[3]{a^2}}{\sqrt[3]{a} \times \sqrt[3]{a^2}}\]Simplifying the denominator, we obtain:\[\frac{2 \sqrt[3]{a^2}}{a}\]
04
Simplify the Expression
The expression \( \frac{2 \sqrt[3]{a^2}}{a} \) is simplified such that the denominator is now a rational number \( a \), and the entire expression is simplified as much as possible while keeping the denominator rationalized.
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.
Cube Roots
The cube root of a number is a special value that, when multiplied by itself three times, gives the original number. It is symbolized as \( \sqrt[3]{x} \). For example, \( \sqrt[3]{8} = 2 \) because \( 2 \times 2 \times 2 = 8 \). In our original problem, we have \( \sqrt[3]{a} \), which is the cube root of \( a \). This tells us:
- If you raise this cube root to the power of three, you'll get the original number \( a \).
- Cube roots help in simplifying expressions and are vital when working with cube-shaped values in geometry or for finding dimensions.
- Unlike square roots, every real number has a real cube root, which can be positive or negative.
Rational Numbers
In mathematics, a rational number is any number that can be expressed as the quotient or fraction \( \frac{p}{q} \) of two integers, with the numerator \( p \) and the denominator \( q \), where \( q eq 0 \). Rational numbers include integers, fractions, and finite or repeating decimals.
- They are called 'rational' since they can be written as a ratio.
- The number \( a \) in the denominator, after rationalizing \( \sqrt[3]{a} \), is a rational number because it can be expressed as \( \frac{a}{1} \).
- Converting complex roots in the denominator into rational numbers simplifies expressions, making equations easier to work with.
Algebraic Expressions
Algebraic expressions combine numbers, variables, and arithmetic operations to create a new value or equation. An expression like \( \frac{2}{\sqrt[3]{a}} \) contains both a number (2) and a variable part (\( \sqrt[3]{a} \)). This highlights a few important aspects:
- Variables represent numbers and allow expressions to describe a set of numbers rather than a single value.
- Simplifying algebraic expressions often involves rationalizing denominators, which means removing irrational numbers from the bottom of a fraction.
- In our exercise, multiplying by \( \sqrt[3]{a^2} \) helps to transform \( \sqrt[3]{a} \) into \( a \), achieving a neat algebraically simplified expression \( \frac{2 \sqrt[3]{a^2}}{a} \).