#(a - b) (a + b) not equal A^2 - B^2 in matrix why is that ?

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fast oceanBOT
hollow locust
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because in matrix position matte

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r

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so lets say if i were to expand (a-b)(a+b)

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i would get a^2+ab-ba -b^2

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u ssually when it is not matrix ab and ba is the same

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but in matrix position matter so ab and ba value wont be the sma

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so let say for example

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if i were to multiply AB i would get

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and if i multiply BA

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I WOULD GET

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so AB is diff from BA thus i=when they are substracted will not =0

spring echo
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(a-b)(a+b)

= a * a + a * b - b * a - b * b

When a and b are numbers, a * b and b * a are equal so they simplify

However in matrices AB is not always equal to BA