SOLUTION: I need help figuring this factoring problem out. Factor completely 27a^4-125a Thanks for all your help. I really appreciate it!

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Question 204280: I need help figuring this factoring problem out.
Factor completely
27a^4-125a
Thanks for all your help. I really appreciate it!
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Factor completely:
27a%5E4-125a First factor out an a.
a%2827a%5E3-125%29 Do you see the difference of cubes in the parentheses?
Do you also recall that:
A%5E3-B%5E3+=+%28A-B%29%28A%5E2%2BAB%2BB%5E2%29, so we have...
27a%5E4-125a+=+highlight%28a%283a-5%29%289a%5E2%2B15a%2B25%29%29