已知一元二次方程请你选取一个适当的的值,使方程能用直接开平方法求解,并解这个方程...

求解矩阵方程AX=B

解: (A,B) = 2 1 -3 1 -1 1 2 2 2 0-1 3 2 -2 5r1-2r2, r3 r2 0 -3 -7 -3 -1 1 2 2 2 0 0 5 4 0 5r3 2r1 0 -3 -7 -3 -1 1 2 2 2 0 0 -1 -10 -6 3r1-3r3, r2 2r3 0 0 23 15 -10 1 0 -18 -10 6 0 -1 -10 -6 3r1*(1/23), r3*(-1) 0 0 1 15/23 -10/23 1 0 -18 -10 6 0 1 10 6 -3r2...全部

  解: (A,B) = 2 1 -3 1 -1 1 2 2 2 0-1 3 2 -2 5r1-2r2, r3 r2 0 -3 -7 -3 -1 1 2 2 2 0 0 5 4 0 5r3 2r1 0 -3 -7 -3 -1 1 2 2 2 0 0 -1 -10 -6 3r1-3r3, r2 2r3 0 0 23 15 -10 1 0 -18 -10 6 0 -1 -10 -6 3r1*(1/23), r3*(-1) 0 0 1 15/23 -10/23 1 0 -18 -10 6 0 1 10 6 -3r2 18r1,r3-10r1 0 0 1 15/23 -10/23 1 0 0 40/23 -42/23 0 1 0 -12/23 31/23交换行得 1 0 0 40/23 -42/23 0 1 0 -12/23 31/23 0 0 1 15/23 -10/23所以 B = 40/23 -42/23-12/23 31/23 15/23 -10/23。
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