difference of 2 cubes formula .. help a homie out lol
2007-02-11 18:15:48 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
i messed up the question before ... its a minus not a plus ... just looking for the factoring formula
2007-02-11 18:17:52 · update #1
(a - b) (a^2 + ab + b^2)
= a(a^2 + ab + b^2) - b(a^2 + ab + b^2)
= a^3 + (a^2)b + a(b^2) - b(a^2) - a(b^2) - b^3
= a^3 + [(a^2)b - b(a^2)] + [a(b^2) - a(b^2)] - b^3
= a^3 + 0 + 0 - b^3
= a^3 - b^3
2007-02-11 18:20:59 · answer #1 · answered by alsh 3 · 2⤊ 0⤋
a^3 - b^3 = (a - b) (a^2 + ab + b^2)
a^3 - b^3 = a^3 + [a{(b^2) - (b^2)}] + [b{(a^2) - (a^2)}] - b^3
= a^3 + [a(b^2) - a(b^2)] + [(a^2)b - b(a^2)] - b^3
= a^3 + (a^2)b + a(b^2) - b(a^2) - a(b^2) - b^3
= a(a^2 + ab + b^2) - b(a^2 + ab + b^2)
= (a - b) (a^2 + ab + b^2)
2007-02-11 18:33:56 · answer #2 · answered by Praful M Nimbargi 2 · 1⤊ 0⤋
(a-b)(a^2+ab + b^2)
2007-02-11 18:25:06 · answer #3 · answered by verbalise 4 · 1⤊ 0⤋
(a-b)(a^2+ab + b^2)
2007-02-11 18:22:18 · answer #4 · answered by lizzie 3 · 1⤊ 0⤋
a^3 + b^3 = a^3 + 3a^2b + 3ab^2 + b^3
2007-02-11 18:22:01 · answer #5 · answered by muredhawk 2 · 0⤊ 3⤋