SOLUTION: please help me factor this polinomial 8a^3-27

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Question 421062: please help me factor this polinomial 8a^3-27
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

8a%5E3-27

2%5E3%2Aa%5E3-3%5E3
%282a%29%5E3-3%5E3........factoring a%5E3+-+b%5E3
an expression of the form a%5E3+-+b%5E3 is called a difference of cubes, the factored form of a+%5E3+-+b%5E+3 is %28a+-+b%29%28a+%5E2+%2B+ab+%2B+b%5E+2%29
so, apply this and you will have
%282a-3%29%28%282a%29%5E2%2B2a%2A3%2B3%5E2%29
%282a-3%29%284a%5E2%2B6a%2B9%29