SOLUTION: Please give me the written proof of (a+b)^3

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Question 910254: Please give me the written proof of (a+b)^3
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Proof of what?
Do you mean you want the expansion?
%28a%2Bb%29%5E3=%28a%2Bb%29%5E2%28a%2Bb%29
%28a%2Bb%29%5E3=a%28a%2Bb%29%5E2%2Bb%28a%2Bb%29%5E2
So,
%28a%2Bb%29%5E2=%28a%2Bb%29%28a%2Bb%29
%28a%2Bb%29%5E2=a%28a%2Bb%29%2Bb%28a%2Bb%29
%28a%2Bb%29%5E2=%28a%5E2%2Bab%29%2B%28ab%2Bb%5E2%29
%28a%2Bb%29%5E2=a%5E2%2B2ab%2Bb%5E2
So then,
%28a%2Bb%29%5E3=a%28a%2Bb%29%5E2%2Bb%28a%2Bb%29%5E2
%28a%2Bb%29%5E3=a%28a%5E2%2B2ab%2Bb%5E2%29%2Bb%28a%5E2%2B2ab%2Bb%5E2%29
%28a%2Bb%29%5E3=%28a%5E3%2B2a%5E2b%2Bab%5E2%29%2B%28a%5E2b%2B2ab%5E2%2Bb%5E3%29
%28a%2Bb%29%5E3=a%5E3%2B3a%5E2b%2B3ab%5E2%2Bb%5E3