SOLUTION: factor each expression: x^3 + 64

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Question 119397: factor each expression:

x^3 + 64
Found 2 solutions by jim_thompson5910, checkley71:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

x%5E3%2B64 Start with the given expression.


%28x%29%5E3%2B%284%29%5E3 Rewrite x%5E3 as %28x%29%5E3. Rewrite 64 as %284%29%5E3.


%28x%2B4%29%28%28x%29%5E2-%28x%29%284%29%2B%284%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


%28x%2B4%29%28x%5E2-4x%2B16%29 Multiply


So x%5E3%2B64 factors to %28x%2B4%29%28x%5E2-4x%2B16%29.

In other words, x%5E3%2B64=%28x%2B4%29%28x%5E2-4x%2B16%29

Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
x^3+64
(x+4)(x^2-4x-16)