Answer:
[tex] {x}^{4} - 3 {x}^{3} - 19 {x}^{2} + 3x + 18[/tex]
Step-by-step explanation:
If a is a zero of a polynomial then
[tex](x - a)[/tex]
is a factor of the polynomial.
So since, -1, 1 ,6 are thr zeroes, then the factors is
[tex](x + 1)(x - 1)(x - 6)[/tex]
[tex]( {x}^{2} - 1)(x - 6)[/tex]
[tex] {x}^{3} - 6 {x}^{2} - x + 6[/tex]
We aren't done because we have a degree of 3 and a constant of 6.
Since we want a constant term 18, and a additional degree, we multiply by another binomial.
which will be
(x+3),
[tex] ({x}^{3} - 6 {x}^{2} - x + 6)(x + 3)[/tex]
[tex] {x}^{4 } - 6 {x}^{3} - {x}^{2} + 6x + 3 {x}^{3} - 18 {x}^{2} - 3x + 18[/tex]
Which simplified gives us
[tex] {x}^{4} -3 {x}^{3} - 19 {x}^{2} + 3x + 18[/tex]