SOLUTION: Please help. (2-9x^3)^2

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Question 124417: Please help.
(2-9x^3)^2
Found 2 solutions by checkley71, jim_thompson5910:
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
2-9X^3
2-9X^3
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4-18X^3-18X^3+81X^6
4-36X^3+81X^6 ANSWER.

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

%282-9x%5E3%29%5E2 Start with the given expression


%282-9x%5E3%29%282-9x%5E3%29 Expand. Remember something like x%5E2=x%2Ax


Now let's FOIL the expression



Remember, when you FOIL an expression, you follow this procedure:


%28highlight%282%29-9x%5E3%29%28highlight%282%29-9x%5E3%29 Multiply the First terms:%282%29%2A%282%29=4


%28highlight%282%29-9x%5E3%29%282%2Bhighlight%28-9x%5E3%29%29 Multiply the Outer terms:%282%29%2A%28-9x%5E3%29=-18x%5E3


%282%2Bhighlight%28-9x%5E3%29%29%28highlight%282%29-9x%5E3%29 Multiply the Inner terms:%28-9x%5E3%29%2A%282%29=-18x%5E3


%282%2Bhighlight%28-9x%5E3%29%29%282%2Bhighlight%28-9x%5E3%29%29 Multiply the Last terms:%28-9x%5E3%29%2A%28-9x%5E3%29=81x%5E6


4-18x%5E3-18x%5E3%2B81x%5E6 Now collect every term to make a single expression



-36x%5E3%2B81x%5E6%2B4 Now combine like terms


81x%5E6-36x%5E3%2B4 Rearrange the terms in descending order


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Answer:
So %282-9x%5E3%29%5E2 foils and simplifies to 81x%5E6-36x%5E3%2B4

In other words, %282-9x%5E3%29%5E2=81x%5E6-36x%5E3%2B4