SOLUTION: How do I expand (x+1)^3 I need to know the rule for expanding cubed brackets in general. Thanks so much!

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Question 882636: How do I expand (x+1)^3
I need to know the rule for expanding cubed brackets in general.
Thanks so much!

Answer by josgarithmetic(39627) About Me  (Show Source):
You can put this solution on YOUR website!
You could either look-up the rule or derive the rule yourself.
Start with %28a%2Bb%29%5E3, and fully multiply to get the resulting product sum of terms. Also, read about Pascal's Triangle.

The shortcut uses coefficients 1, 3, 3, 1;
The terms containing a start with a%5E3, and each term increases by 1 in degree on b while decreases by 1 on the degree for a.

You should find 1%2Aa%5E3%2B3%2Aa%5E2b%2B3%2Ab%5E2a%2B1%2Ab%5E3;
More simply a%5E3%2B3a%5E2b%2B3ab%5E2%2Bb%5E3