Question

$2 {x}^{3} + 3 {x }^{2} - 18x - 27$How do i do this?

Answer 1

to find the x-intercepts we need to equal the expression to 0. So we get that

$\begin{gathered} 2x^3+3x^2-18x-27=0 \\ 2x^3-18x+3x^2-27=0 \\ 2x(x^2-9)+3(x^2-9)=0 \\ (2x+3)(x^2-9)=0 \\ (2x+3)(x-3)(x+3)=0 \end{gathered}$

so the x-intercepts are x=-3/2, x=3 and x=-3