Tolong dijawab yaa..

[tex]f(x) = 2 {x}^{3} + 3 {x}^{2} + ax - 3 \\ s(3) = 54 + 27 + 3a - 3 = 18 \\ 3a = - 60 \\ a = - 20 \\ f(x) = 2 {x}^{3} + 3 {x}^{2} - 20x - 3 \: \div (x - 3) = \\ 2 {x}^{2} + 9x + 7[/tex]