SOLUTION: Factor completely: y^3-8 Thank you for your help and time !!!

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Question 52755: Factor completely:
y^3-8
Thank you for your help and time !!!
Found 2 solutions by funmath, Nate:
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
The formula for factoring the difference of two perfect cubes is:
a%5E3-b%5E3=%28a-b%29%28a%5E2%2Bab%2Bb%5E2%29
y%5E3-8%29=%28y%2Ay%2Ay-2%2A2%2A2%29
Therefore we have:
y%5E3-2%5E3
a=y and b=2 Plug them into your formula and you have:
y%5E3-8=%28y-2%29%28y%5E2%2By%2A2%2B2%5E2%29
y%5E3-8=highlight%28%28y-2%29%28y%5E2%2B2y%2B4%29%29
Happy Calculating!!!

Answer by Nate(3500) About Me  (Show Source):
You can put this solution on YOUR website!
y^3 - 8
(y)^3 - (2)^3 = (y - 2)(y^2 + 2y + 4)
~> y^3 - 2y^2 + 2y^2 - 4y + 4y - 8 ~> y^3 - 8