求基础解系时，系数矩阵能不能某一行同时乘或除？不是矩阵乘或除要对整个矩阵的吗，怎么书上其中一行同时 求解X 请问矩阵在进行初等行变换的时候，某行可以乘或者除一个...
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\u884c\u53d8\u6362\uff0c\u4e0d\u6539\u53d8\u5217\u5411\u91cf\u4e4b\u95f4\u7684\u76f8\u5173\u6027\u3002
\u4e0d\u4ec5\u5305\u62ec\u76f8\u5173/\u4e0d\u76f8\u5173\uff0c\u8fd8\u5305\u62ec\u5411\u91cf\u7684\u7ebf\u6027\u8868\u793a\u7cfb\u6570\u3002
\u6240\u4ee5\uff0c\u8fd9\u4e2a\u89e3\u4e0d\u53d8\u3002
\u8fd9\u4e48\u8bf4\u4e5f\u8bb8\u62bd\u8c61\u4e00\u70b9\u3002
\u56de\u60f3\u521d\u4e2d\u7684\u89e3\u591a\u5143\u4e00\u6b21\u65b9\u7a0b\u7ec4\uff0c\u67d0\u4e2a\u65b9\u7a0b\u4e24\u8fb9\u540c\u4e58\u4ee5\u67d0\u4e2a\u4e0d\u7b49\u4e8e0\u7684\u7cfb\u6570\uff08\u8fd9\u4e0d\u5c31\u662f\u7cfb\u6570\u77e9\u9635\u67d0\u884c\u4e58\u4e00\u4e2a\u6570\u4e48\uff1f\uff09\uff0c\u662f\u4e0d\u662f\u4e0d\u6539\u53d8\u65b9\u7a0b\u7ec4\u7684\u89e3\uff1f
\u540c\u7406\uff0c\u4e24\u4e2a\u65b9\u7a0b\u4e24\u8fb9\u76f8\u52a0\uff08\u5bf9\u5e94\u884c\u53d8\u6362\uff1a\u628a\u67d0\u884c\u52a0\u5230\u53e6\u4e00\u884c\u4e0a\uff09\uff0c\u4e5f\u4e0d\u6539\u53d8\u7ebf\u6027\u65b9\u7a0b\u7ec4\u7684\u89e3\u3002
\u5316\u6210 AX=B \u7684\u5f62\u5f0f
\u7528\u521d\u7b49\u884c\u53d8\u6362\u5c06 (A,B) \u5316\u4e3a (E,X)
\u53ef\u4ee5\u4e58\u4efb\u4e00\u4e2a\u975e\u96f6\u5e38\u6570(\u4e0d\u52a0\u5230\u53e6\u4e00\u884c\u4e0a)
求解线性方程组时, 用的是矩阵的初等变换, 一般用行变换
初等行变换有3种:
1.交换两行
2.某行乘非零数k
3.某行的k倍加到另一行
你说的变换是第2种.
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绛旓細r(A)=1 锛屽熀纭瑙ｇ郴鐨勮В鍚戦噺鐨勪釜鏁颁负 3-1 =2 浠2=1锛寈3=0锛屽緱x1=-1锛屛1=(-1锛1锛0)T 浠2=0锛寈3=1锛屽緱x1=1锛屛2=(1锛0锛1)T 鍩虹瑙ｇ郴涓猴紝伪1锛屛2 newmanhero 2015骞6鏈6鏃17:17:43 甯屾湜瀵逛綘鏈夋墍甯姪锛屾湜閲囩撼銆
绛旓細r(A) =1 锛屽熀纭瑙ｇ郴鐨勮В鍚戦噺鐨勪釜鏁颁负 3-1 =2 浠2=1锛寈3=0锛屽緱x1=-1锛屛1=(-1锛1锛0)T 浠2=0锛寈3=1锛屽緱x1=1锛屛2=(1锛0锛1)T 鍩虹瑙ｇ郴涓猴紝伪1锛屛2 鍐欏嚭绯绘暟鐭╅樀涓 2 -1 1 -1 2 -1 0 -3 0 1 3 -6 2 -2 -2 5 r2-r1锛宺4-r1锛宺1+r3 ~2 0 4 -7...
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