SOLUTION: x^3 – 1331 please show how to factor

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Question 636652: x^3 – 1331 please show how to factor
Found 2 solutions by MathLover1, PkGeci:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
you need to use this rule:


a%5E3-b%5E3=%28a-b%29%28a%5E2%2Bab%2Bb%5E2%29


x%5E3-1331=x%5E3-11%5E3=%28x-11%29%28x%5E2%2B11x%2B121%29

Answer by PkGeci(6) About Me  (Show Source):
You can put this solution on YOUR website!
its trial and error but you need to find a number that if its raised to the power of 3 will give you 1331. In this case its 11^3
Now You can rewrite your equation using the newly found number.
x^3=11^3 since both side is to the power of 3 you can get ride of the powers.
x=11 is your final answer!