Matlab利用矩阵运算解方程组的编程 急急急！关于用matlab计算矩阵或编程计算矩阵。
MATLAB\u7f16\u7a0b\u89e3\u65b9\u7a0b\u7ec4\u3002\u3002\u5199\u51faMATLAB\u7a0b\u5e8fA=[3,2,5;-1,4,3;1,-1,3];
B=[6;5;1];
X=inv(A)*B
\u7ed3\u679c\uff1a
X =
0.5000
1.0000
0.5000
\u5373\u7528\u77e9\u9635\u7684\u4e58\u9664\u6cd5\uff08\u8fd9\u91cc\u7528\u7684\u662f\u9006\u77e9\u9635)\u6765\u8ba1\u7b97\u3002
\u6216\u8005\u7528MATLAB\u81ea\u5df1\u7684solve\u51fd\u6570\u6765\u8ba1\u7b97
syms x1 x2 x3;
[x1,x2,x3]=solve('3*x1+2*x2+5*x3=6','-x1+4*x2+3*x3=5','x1-x2+3*x3=1')
\u7ed3\u679c\u4e3a\uff1a
x1 =
1/2
x2 =
1
x3 =
1/2
\u7528 Maple \u53ef\u4ee5\u505a\u5982\u4e0b\u8ba1\u7b97\uff1a
1\u3001\u8bbeA\u4e3a\u4e0a\u4e09\u89d2\u77e9\u9635\uff0cB\u4e3aA \u7684\u8f6c\u7f6e\u77e9\u9635\uff1b
2\u3001\u7ee7\u7eed\uff0c\u8bbeC\u4e3a\u5df2\u77e5\u77e9\u9635\u5e76\u8d4b\u503c\uff0c\u8ba1\u7b97A.B-C\uff08\u6b64\u4f8b\u4e2d\uff0c\u7531\u8be5\u5df2\u77e5\u77e9\u9635\u53ef\u4ee5\u7b97\u5f97\u6574\u6570\u7684\u7ed3\u679c\uff09\uff1b
3\u3001\u6c42\u89e3\u8be5\u77e9\u9635\u65b9\u7a0b\uff0c\u5f97abcdef\u7684\u503c\u3002
4\u3001\u6700\u540e\u8be5\u4f8b\u89e3\u5f97\u5171\u67098\u7ec4\u89e3\uff0c\u5982\u4e0a\u3002
5\u3001\u6362\u6210\u5176\u4ed6\u7684\u5df2\u77e5\u77e9\u9635\u4e5f\u53ef\u4ee5\u89e3\uff0c\u4f46\u89e3\u7684\u5f62\u5f0f\u76f8\u5e94\u7684\u8981\u590d\u6742\u5f88\u591a\uff0c\u4f8b\u5982\u5c06C[2,2]\u6362\u621059\u540e\uff0c\u89e3\u5982\u4e0b\uff1a
\u9700\u8981\u6ce8\u610f\uff0c\u5e76\u4e0d\u662f\u4efb\u610f\u7684\u5df2\u77e5C\u90fd\u6709\u7ed3\u679c\u3002
x=A\b
例如，对上面的问题，源程序如下：
A=[1 2 1;2 1 -2;3 -4 2];
b=[1 3 9]';
x=A\b
结果为：
x =
2.0270
-0.6216
0.2162
即为x、y、z的值
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