SOLUTION: 3x^3 + 81 i just cant figure it out its been all day

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Question 3677: 3x^3 + 81 i just cant figure it out its been all day
Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
what do you want? to factorise it?

3%28x%5E3+%2B+27%29
3%28x%5E3+%2B+3%5E3%29

now, a%5E3+%2B+b%5E3 is equivalent to %28a%2Bb%29%28a%5E2-ab%2Bb%5E2%29, so for ours, we get:

3%28x%2B3%29%28x%5E2-3x%2B9%29

jon.