Skip to main content
Ch. P - Fundamental Concepts of Algebra
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 1, Problema 64

In Exercises 33–68, add or subtract as indicated. x/(x2−2x−24) − x/(x2−7x+6)

Guida verificata passo dopo passo
1
Factorize the denominators of both fractions. For the first denominator, \(x^2 - 2x - 24\), find two numbers that multiply to \(-24\) and add to \(-2\). For the second denominator, \(x^2 - 7x + 6\), find two numbers that multiply to \(6\) and add to \(-7\).
Rewrite the fractions with the factored denominators. The first fraction becomes \(\frac{x}{(x - 6)(x + 4)}\), and the second fraction becomes \(\frac{x}{(x - 6)(x - 1)}\).
Identify the least common denominator (LCD) of the two fractions. The LCD is the product of all unique factors in the denominators: \((x - 6)(x + 4)(x - 1)\).
Rewrite each fraction with the LCD as the denominator. Multiply the numerator and denominator of the first fraction by \((x - 1)\), and the numerator and denominator of the second fraction by \((x + 4)\). This gives \(\frac{x(x - 1)}{(x - 6)(x + 4)(x - 1)}\) and \(\frac{x(x + 4)}{(x - 6)(x + 4)(x - 1)}\).
Combine the fractions by subtracting the numerators over the common denominator. Simplify the numerator \(x(x - 1) - x(x + 4)\) and leave the denominator as \((x - 6)(x + 4)(x - 1)\).

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
2m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Factoring Polynomials

Factoring polynomials involves rewriting a polynomial expression as a product of its factors. This is essential for simplifying expressions and finding common denominators in rational expressions. For example, the quadratic expressions in the denominators, x^2 - 2x - 24 and x^2 - 7x + 6, can be factored to facilitate addition or subtraction.
Video consigliato:
07:30
Introduction to Factoring Polynomials

Common Denominator

A common denominator is a shared multiple of the denominators of two or more fractions. When adding or subtracting rational expressions, it is necessary to express each fraction with the same denominator to combine them effectively. In this case, finding the least common denominator (LCD) of the two factored expressions is crucial for performing the operation.
Video consigliato:
02:58
Rationalizing Denominators

Rational Expressions

Rational expressions are fractions where the numerator and the denominator are polynomials. Understanding how to manipulate these expressions, including addition, subtraction, multiplication, and division, is fundamental in algebra. In this problem, the operation involves subtracting two rational expressions, which requires careful handling of the numerators and the common denominator.
Video consigliato:
02:58
Rationalizing Denominators