Question 819497
Write a third degree polynomial function y=P(x) with rational coefficients so that P(x)=0 has the given roots. 
1, 2-i and 2+i
-----
P(x) = (x-1)(x-2+i)(x-2-i)
----
= (x-1)[(x-2)+i)(x-2)-i)]
----
= (x-1)[(x-2)^2+1]
----
= (x-1)(x^2-4x+5)
----
= x^3 - 5x^2 + 9x -5
======================
Cheers,
Stan H.
=======================


 
3, 6+i 
3i, 7 
1, 5i 
3, -4i