Question 458644
{{{P(x) = (x^2 + 9)(x + 3)}}}

{{{P(x) = (x^2 + 3^2)(x + 3)}}}..........

we can factor {{{x^2+3^2}}} like this:

{{{x^2+3^2=x^2-3^2(-1)=x^2-3^2(i^2)=x^2-(3i)^2)=(x-3i) (x+3i)}}}...substitute

{{{P(x) = (x-3i) (x+3i)(x + 3)}}}

so, solutions are:

{{{x-3i=0}}}....->..... {{{x=3i}}}

{{{x+3i=0}}}....->..... {{{x=-3i}}}

{{{x+3=0}}}....->..... {{{x=-3}}}

here is a graph for {{{P(x) = (x^2 + 9)(x + 3)=x^3+3x^2+9x+27}}}:

{{{ graph( 500, 500, -50, 60, -50, 60, x^3+3x^2+9x+27) }}}