complex numbers, like radicals, always come in their conjugate form
so if -2i is a zero so is +2i
so f(x) = (x-1)(x-2)(x - 2i)(x + 2i)
the last two factors multiply for x^4 + 4
f(x) = (x-1)(x-2)(x^4 + 4)
expand if needed, I like it the way it is.
write a polynomial function in standard form with the given zeros. 1-2i,2
3 answers
no comma there actually
zero when
x = 1-2i
x = 1+2i
x = 2
so I get
(x-2)(x-1+2i)(x-1-2i)
(x-2) (x^2-2x+5)
zero when
x = 1-2i
x = 1+2i
x = 2
so I get
(x-2)(x-1+2i)(x-1-2i)
(x-2) (x^2-2x+5)
Just have to get stronger glasses.