Question

solve the b) , and please with details

Answer 1

Let's put the general multiplier outside the brackets

$2x^3-x^2-18x+9=(2x^3-x^2)-(18x-9)=\\ \\ =x^2(2x-1)-9(2x-1)=(2x-1)(x^2-9)=\\ \\ =(x-3)(x+3)(2x-1)=(x-3)(2x^2+5x-3)\\ \\ where\,\,\,\, a=2;\,\,\,\, b=5;\,\,\,\, c=-5$