How do you find all zeros of the function $f(x) = x^3 + x^2 - 12x$ ?

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Answer 1 · 2016-11-02T19:03:09

$f(x)$ has zeros $x=0$ , $x=-4$ and $x=3$

$f(x) = x^3+x^2-12x$

Note that $4*3 = 12$ and $4-3=1$

Hence we find:

$x^3+x^2-12x = x(x^2+x-12) = x(x+4)(x-3)$

So $f(x)$ has zeros $x=0$ , $x=-4$ and $x=3$

How do you find all zeros of the function f(x) = x^3 + x^2 - 12xf(x) = x^3 + x^2 - 12x?