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Ch. 5 - Systems of Equations and Inequalities
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 6, Problema 81

Solve: x4+2x3−x2−4x−2=0

Guida verificata passo dopo passo
1
Start by examining the polynomial equation x4 + 2x3 - x2 - 4x - 2 = 0 to see if it can be factored by grouping or by using substitution.
Try to group terms to factor: group the first two terms and the last three terms separately, like this: (x4 + 2x3) + (- x2 - 4x - 2). Then factor out the greatest common factor (GCF) from each group.
After factoring by grouping, check if the resulting expression can be factored further into the product of two quadratic polynomials, such as (x^2 + ax + b)(x^2 + cx + d) = 0. Set up equations by expanding and matching coefficients to find the values of a, b, c, and d.
Once the polynomial is factored into two quadratics, set each quadratic equal to zero: x^2 + ax + b = 0 and x^2 + cx + d = 0. Solve each quadratic equation using the quadratic formula: x = \(\frac{-B \pm \sqrt{B^2 - 4AC}\)}{2A}, where A, B, and C are the coefficients of the quadratic.
Write down all the solutions obtained from the quadratic equations. These solutions are the roots of the original quartic equation.

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