(a-b)的三次方,等于多少啊？ (a-b)的三次方等于多少
(a-b)\u7684\u4e09\u6b21\u65b9,\u7b49\u4e8e\u591a\u5c11\u554a\u516c\u5f0f\u56fe\u5f62\u5316\uff0ca+b\u7684\u548c\u7684\u4e09\u6b21\u65b9
\u8fd9\u4e2a\u5f0f\u5b50\u53ef\u4ee5\u76f4\u63a5\u5316\u7b80\u6765\u7b97\uff0c\u5c06(a-b)³\u5206\u89e3\u662f\u4e00\u4e2a\u5e73\u65b9\u5dee\u548c\u4e00\u4e2a\u51cf\u6570\u76f8\u4e58
(a-b)³=(a-b)²(a-b)
\u6700\u540e=a³-3a²b+3ab²-b³
\u6269\u5c55\u8d44\u6599
\u5b8c\u5168\u7acb\u65b9\u5dee\u516c\u5f0f\u662f\u4e00\u4e2a\u6570\u5b66\u516c\u5f0f\uff0c\u5373(a-b)³=a³-3a²b+3ab²-b³
\u7acb\u65b9\u548c\u516c\u5f0f
\u7acb\u65b9\u5dee\u516c\u5f0f
\u4e09\u9879\u7acb\u65b9\u548c\u516c\u5f0f
\u5b8c\u5168\u7acb\u65b9\u516c\u5f0f
\u7f16\u8f91
(a-b)³=a³+3ab²-3a²b-b³
\u5206\u89e3\u6b65\u9aa4\u5982\u4e0b
(a+b)3=(a+b)(a+b)(a+b) = (a2+2ab+b2)(a+b)=a3+3a2b + 3ab2+ b3
\u89e3\u9898\u65f6\u5e38\u7528\u5b83\u7684\u53d8\u5f62\uff1a
(a+b)3= a3+ b3+ 3ab(a+b)\u3000\u548c\u3000a3+ b3= (a+b)3- 3ab(a+b)
(a-b)³=(a-b)(a-b)(a-b)=(a²-2ab+b²)(a-b)=a³-3a²b+3ab²-b³
\u7acb\u65b9\u548c\u7d2f\u52a0
\u6b63\u6574\u6570\u8303\u56f4\u4e2d
\u6ce8\uff1a\u53ef\u7528\u6570\u5b66\u5f52\u7eb3\u6cd5\u8bc1\u660e
\u53c2\u8003\u8d44\u6599\u767e\u5ea6\u767e\u79d1-\u5b8c\u5168\u7acb\u65b9\u5dee\u516c\u5f0f
(a-b)(a-b)(a-b)
=a*3-3a*2b+3ab*2-b*3.
(其中*3表示3次方， *2表示2次方）。
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