SOLUTION: Find the product of (4+5i) and (4-5i) What are pairs of complex numbers like these called?

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Question 685129: Find the product of (4+5i) and (4-5i) What are pairs of complex numbers like these called?
Answer by funmath(2933) About Me  (Show Source):
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Find the product of (4+5i) and (4-5i) What are pairs of complex numbers like these called?
These are called "conjugates" of each other because they are the same binomials with opposite signs in the middle.
You need to know that highlight%28i%5E2=-1%29 then you can foil as always...but conjugates always multiply to be the difference of squares...so it is not necessary...but it works every time.
%284%2B5i%29%284-5i%29
4%284-5i%29%2B5i%284-5i%29
16-20i%2B20i-25i%5E2
16-25i%5E2
The above is the difference of squares that you can skip to for conjugates.
16-25%28-1%29
16%2B25
highlight%2841%29
Happy Calculating!!!