SOLUTION: I'm trying to figure out this problem by the sum of cubes (a+b)^3+64 Can anyone explain it in steps? Thank you so much

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Question 726626: I'm trying to figure out this problem by the sum of cubes
(a+b)^3+64
Can anyone explain it in steps?
Thank you so much
Found 2 solutions by tanjo3, lwsshak3:
Answer by tanjo3(60) About Me  (Show Source):
You can put this solution on YOUR website!
I'm not sure what you mean but if you want to expand the equation then:


%28a%2Bb%29%5E3+%2B+64+=+a%5E3+%2B+3a%5E2b+%2B+3ab%5E2+%2B+b%5E3+%2B+64

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
I'm trying to figure out this problem by the sum of cubes
(a+b)^3+64
***
Formula for sum of cubes: (x+y)^3=(x+y)(x^2-xy+y^2)
For given problem:
64=4^3
(a+b)^3+64 =(a+b)^3+4^3
=((a+b)+4)((a+b)^2-(a+b)*4+4^2)
=(a+b+4)(a^2+2ab+b^2-4a-4b+16)