You can put this solution on YOUR website! (x+3)^3
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It is NOT x^3 + 27
To prove that x^3 + 27 is not right:
Let x = 1
(1 + 3)^3 = 64
1^3 + 3^3 = 28
Not equal. It has to be equal for all values of x
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You can multiply it out a step at a time:
= (x+3)*(x+3)*(x+3)
= (x+3)*(x^2 + 6x + 9)
= as above
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Or use Pascal's triangle:
1
1 2 1
1 3 3 1
(a+b)^3 = a^3 + 3a^2b + 3ab^2 + b^3 (using the 1 3 3 1 coefficients)
a = x, b = 3
--> as above
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