Patrick B. answered 11/18/20
Math and computer tutor/teacher
You did not say the polynomial must have RATIONAL coefficients,
but I will assume you want REAL coefficients...
a)
(x-5)(x - (3 - 2rad7)) =
x^2 - 5x - (3-2rad7)x + 10rad7 =
x^2 - x( 5 + (3-2rad7)) + 10rad7 =
x^2 - (8-2rad7)x + 10 rad7
Now, if you want RATIONAL coefficients:
(x-5) [(x - 3)-2rad7] [(x-3)+2rad7] =
(x-5) [ (x-3)^2 - 4*7] =
(x-5) [ (x^2 -6x + 9 - 28]=
(x-5) [ x^2 - 6x - 19]
(b) (x-2)(x-3) [( x-1)-i][ (x-1)+i]=
(x-2)(x-3) [ (x-1)^2+1] =
(x-2)(x-3) [ x^2 -2x +2] =
(x^2 -5x+6)(x^2-2x+2) =