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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 32

In Exercises 15–32, multiply or divide as indicated. (x3−25x)/4x2 ⋅ (2x2−2)/(x2−6x+5) ÷ (x2+5x)/(7x+7)

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Factorize all the polynomials in the given expression. For the numerator and denominator of the first fraction: \(x^3 - 25x\) can be factored as \(x(x^2 - 25)\), and \(x^2 - 25\) can be further factored as \((x - 5)(x + 5)\). The denominator \(4x^2\) remains as is.
For the second fraction: \(2x^2 - 2\) can be factored as \(2(x^2 - 1)\), and \(x^2 - 1\) can be further factored as \((x - 1)(x + 1)\). The denominator \(x^2 - 6x + 5\) factors as \((x - 5)(x - 1)\).
For the third fraction (which is part of the division): \(x^2 + 5x\) can be factored as \(x(x + 5)\), and \(7x + 7\) can be factored as \(7(x + 1)\).
Rewrite the division problem as multiplication by the reciprocal of the third fraction. This means flipping the numerator and denominator of the third fraction. The expression becomes: \[ \frac{x(x - 5)(x + 5)}{4x^2} \cdot \frac{2(x - 1)(x + 1)}{(x - 5)(x - 1)} \cdot \frac{7(x + 1)}{x(x + 5)}. \]
Simplify the expression by canceling out common factors in the numerators and denominators. Look for terms such as \(x\), \(x - 5\), \(x + 5\), \(x - 1\), and \(x + 1\) that appear in both the numerator and denominator. After canceling, multiply the remaining terms to get the simplified result.

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