Question

Find a polynomial equation with integral coefficients of lowest degree which has the roots 4 and the double root of -1/3

Answer 1

root 1 =4, that is x -4 is a factor of the polynomial
double root = -1/3, that is (x+1/3) ^2 is another factor of the polynomial
hence the lowest degree is 3, the polynomial is (x-4) (x+1/3)^2. You open it.