SOLUTION: please help me solve this problem. I have to factor it. 8x^3+125

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Question 478688: please help me solve this problem. I have to factor it.
8x^3+125
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

8x%5E3%2B125 Start with the given expression.


%282x%29%5E3%2B%285%29%5E3 Rewrite 8x%5E3 as %282x%29%5E3. Rewrite 125 as %285%29%5E3.


%282x%2B5%29%28%282x%29%5E2-%282x%29%285%29%2B%285%29%5E2%29 Now factor by using the sum of cubes formula. Remember the sum of cubes formula is A%5E3%2BB%5E3=%28A%2BB%29%28A%5E2-AB%2BB%5E2%29


%282x%2B5%29%284x%5E2-10x%2B25%29 Multiply

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Answer:

So 8x%5E3%2B125 factors to %282x%2B5%29%284x%5E2-10x%2B25%29.

In other words, 8x%5E3%2B125=%282x%2B5%29%284x%5E2-10x%2B25%29