SOLUTION: Keller performed the work below to express the polynomial in factored form: r(x) = x^4 - 8x^2 - 9 r(x) = (x^2 + 1)(x^2 - 9) (x) = (x + 1)(x - 1)(x + 3)(x - 3) Exp

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Keller performed the work below to express the polynomial in factored form: r(x) = x^4 - 8x^2 - 9 r(x) = (x^2 + 1)(x^2 - 9) (x) = (x + 1)(x - 1)(x + 3)(x - 3) Exp      Log On


   

Question 1182015: Keller performed the work below to express the polynomial in factored form:
r(x) = x^4 - 8x^2 - 9
r(x) = (x^2 + 1)(x^2 - 9)
(x) = (x + 1)(x - 1)(x + 3)(x - 3)
Explain the error he made and complete the factorization correctly.
Found 2 solutions by josgarithmetic, mananth:
Answer by josgarithmetic(39628) About Me  (Show Source):
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!

r(x) = x^4 - 8x^2 - 9 }}}

+x%5E4+-9x%5E2+%2Bx%5E2+-9
+x%5E2%28x%5E-9%29+%2B1%28x%5E2-9%29
+%28x%5E2-9%29%28x%5E2%2B1%29
%28x%2B3%29%28x-3%29%28x%5E2%2B1%29

(x^2+1) not (x+1)(x-1)







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