Exercise
$-x^4+x^3+28x^2-16x-192$
Step-by-step Solution
Learn how to solve problems step by step online. Factor the expression -x^4+x^328x^2-16x+-192. We can factor the polynomial -x^4+x^3+28x^2-16x-192 using the rational root theorem, which guarantees that for a polynomial of the form a_nx^n+a_{n-1}x^{n-1}+\dots+a_0 there is a rational root of the form \pm\frac{p}{q}, where p belongs to the divisors of the constant term a_0, and q belongs to the divisors of the leading coefficient a_n. List all divisors p of the constant term a_0, which equals -192. Next, list all divisors of the leading coefficient a_n, which equals 1. The possible roots \pm\frac{p}{q} of the polynomial -x^4+x^3+28x^2-16x-192 will then be. Trying all possible roots, we found that 4 is a root of the polynomial. When we evaluate it in the polynomial, it gives us 0 as a result.
Factor the expression -x^4+x^328x^2-16x+-192
Final answer to the exercise
$-\left(x+3\right)\left(x-4\right)^2\left(x+4\right)^2$