Answer:
x^2 - 12x + 37
x^2 + 16
x^2 + 6x + 34
Step-by-step explanation:
Let's expand the first one:-
(x - 6 + i)(x - 6 - i)
= x^2 - 6x - ix - 6x + 36 + 6i + ix - 6i - i^2
= x^2 - 12x -ix + ix - 6i + 6i + 36 - (-1)
= x^2 - 12x + 37 (answer).
(x + 4i)(x - 4i)
= x^2 + 4ix - 4ix -16 i^2
= x^2 + 16 (answer).
(x + 3 + 5i)(x + 3 - 5i)
= x^2 + 3x - 5ix + 3x + 9 - 15i + 5ix + 15i - 25 i^2
= x^2 + 6x + 34. (answer).
