更新1:
pingsuet2003你個answer錯左, 應該係2a(a^2+3b^2), 我想知中間的過程...
factorize (a+b)^3+(a-b)^3
回答 (3)
2008-09-16 4:03 am
✔ 最佳答案
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希望幫到你,
其實你將(a+b)=c, (a-b)=d >>>c^3+d^3
咁你代返D a and b 落條式就得
2008-09-18 3:52 am
(a+b)^3+(a-b)^3
=3(a+b)+3(a-b)
=3a+3b+3a-3b
=6a.
=3(a+b)+3(a-b)
=3a+3b+3a-3b
=6a.
2008-09-16 2:26 am
(a+b)^3+(a-b)^3
=(a^2+2ab+b^2)(a+b)+(a^2-2ab+b^2)(a-b)
=a^3+2a^2b+ab^2+ab^2+2ab^2+b^3+b^3+a^3-2a^2b+ab^2-a^2b+2ab^2-b^2
=2a^3+2ab^2+4ab^2
=(a^2+2ab+b^2)(a+b)+(a^2-2ab+b^2)(a-b)
=a^3+2a^2b+ab^2+ab^2+2ab^2+b^3+b^3+a^3-2a^2b+ab^2-a^2b+2ab^2-b^2
=2a^3+2ab^2+4ab^2
收錄日期: 2021-04-16 23:28:01
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