How do you find all the roots of $f(x) = 3x^2 + 18x + 27$ ?

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Answer 1 · 2016-08-13T23:12:10

$f(x)$ has zero $x=-3$ of multiplicity $2$

$f(x) = 3x^2+18x+27$

$=3(x^2+6x+9)$

$= 3(x^2+2(3)x+3^2)$

$= 3(x+3)^2$

So the zeros of $f(x)$ are both $-3$ , i.e. $x=-3$ is a zero with multiplicity $2$ .

How do you find all the roots of f(x) = 3x^2 + 18x + 27f(x) = 3x^2 + 18x + 27?