So the answers to the quartic equation would be x=3, x=3, x= -2 + √3, and x = -2 - √3
work backwards,
e.g. if you had a quadratic function whose zeros are 3 and -4, wouldn't you have two factors, namely
(x-3) and (x+4), and your equation would have to be y = a(x-3)(x+4) , where is a non-zero constant
which would have no effect on the solution.
so form the 4 factors from the given zeros, (yes , two of them are the same)
and y = a(...)(...)(...)(...)