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Ch. R - Review of Basic Concepts
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 1, Problem 99a

Simplify each rational expression. Assume all variable expressions represent positive real numbers. (Hint: Use factoring and divide out any common factors as a first step.) [2(2x-3)1/3 - (x-1)(2x-3)-2/3] / [(2x-2)-2/3]

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Identify the given rational expression: \(\frac{2(2x-3)^{1/3} - (x-1)(2x-3)^{-2/3}}{(2x-2)^{-2/3}}\).
Factor expressions where possible. Notice that \$2x-2\( can be factored as \)2(x-1)\(, so rewrite the denominator as \)(2(x-1))^{-2/3}$.
Look for common factors in the numerator. Both terms contain powers of \((2x-3)\): \( (2x-3)^{1/3} \) and \( (2x-3)^{-2/3} \). Factor out the smaller power, which is \( (2x-3)^{-2/3} \), from the numerator.
After factoring, the numerator becomes \( (2x-3)^{-2/3} [2(2x-3)^{(1/3 + 2/3)} - (x-1)] = (2x-3)^{-2/3} [2(2x-3)^{1} - (x-1)] \).
Rewrite the entire expression as \( \frac{(2x-3)^{-2/3} [2(2x-3) - (x-1)]}{(2(x-1))^{-2/3}} \). Then, use the property of exponents to rewrite the division as multiplication by the reciprocal, and simplify the expression inside the brackets.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Rational Expressions

Rational expressions are fractions where the numerator and/or denominator are polynomials or algebraic expressions. Simplifying them involves factoring, canceling common factors, and applying algebraic rules to rewrite the expression in a simpler form.
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Exponents and Radicals with Rational Powers

Rational exponents represent roots and powers simultaneously, such as x^(m/n) meaning the n-th root of x raised to the m-th power. Understanding how to manipulate expressions with rational exponents, including negative exponents, is essential for simplification.
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Factoring involves rewriting expressions as products of simpler expressions. Identifying and canceling common factors in the numerator and denominator reduces the expression to its simplest form, which is a key step in simplifying rational expressions.
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