matrix dimension error. i can understand why it is showing but cannot get any solution

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Sat m 2013-3-15

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https://ww2.mathworks.cn/matlabcentral/answers/67271-matrix-dimension-error-i-can-understand-why-it-is-showing-but-cannot-get-any-solution

采纳的回答： Walter Roberson

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i have A1 which 2x2 matrix and B1 which 2x1 matrix. i have a system

A1*Y=B1.

i wish to solve it by

Y = A1/B1;

but it shows

error matrix dimension must agree.

i can understand why it is showing like this, but how to solve this problem?

    A1 = [x1,(r11*X1+r12*Y1+r13*Z1+Tx);x2,(r11*X2+r12*Y2+r13*Z2+Tx)];
    B1 = [-x1*(r31*X1+r32*Y1+r33*Z1);-x2*(r31*X2+r32*Y2+r33*Z2)];
    Y = A1/B1;
    disp(Y);

please let me know

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Answer 1

Walter Roberson 2013-3-15

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Are you sure you want A1/B1 and not A1\B1 ?

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Sat m 2013-3-15

thank you. i am sorry it was my mistake that i did A1/B1 instead of A1\B1. i did not know the difference between / and \ in case of inverse....thank you

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Answer 2

Youssef Khmou 2013-3-15

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编辑：Youssef Khmou 2013-3-15

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hi, you can try :

 % given A AND B 
 A=rand(2);
 B=rand(2,1);
 %1) solution 1: A^-1
 X1=inv(A)*B;
 %2) solution 2 : Pseudo inverse
 X2=pinv(A)*B;
 %3) solution 3 : leastt squares 
 X3=inv(A'*A)*A'*B;
 %4) solution  A\B
 X4=A\B;