Problem with solve matrix

Hi everyone,Can you help me solve this problem

clc
clear all 

disp('An economic system composed of 3 sectors has the input-output matrix');

D=[0.5,0.1,0.1;0.2,0.5,0.3;0.1,0.3,0.4]

disp('The output vector X when the external demands are E');

E=[7900;3950;1975]

disp(['To meet the outside demand,the vector X must satisfy the Leontief equation:' ...
    'X=DX+E =>(I-D)X=E=>X=((I-D)^(-1))E']);
I=[1,0,0;0,1,0;0,0,1]

X = [(I-D)^(-1)]*E

and X=(inv(I-D))*E
 
 but all answer error and don't give right answer X=[27500;33750;24750]

[jose antonio valles]

and, this is you error

[jose antonio valles]

and the last row is repeated "and X=(inv(I-D))*E"

Answer 1

[Stephan]

For me your code works:

disp('An economic system composed of 3 sectors has the input-output matrix');
D=[0.5,0.1,0.1;0.2,0.5,0.3;0.1,0.3,0.4]
disp('The output vector X when the external demands are E');
E=[7900;3950;1975]
disp(['To meet the outside demand,the vector X must satisfy the Leontief equation:' ...
    'X=DX+E =>(I-D)X=E=>X=((I-D)^(-1))E'])
I=[1,0,0;0,1,0;0,0,1]
X = ((I-D)^(-1))*E
X=(inv(I-D))*E

results in:

An economic system composed of 3 sectors has the input-output matrix

D =

    0.5000    0.1000    0.1000
    0.2000    0.5000    0.3000
    0.1000    0.3000    0.4000

The output vector X when the external demands are E

E =

        7900
        3950
        1975

To meet the outside demand,the vector X must satisfy the Leontief equation:X=DX+E =>(I-D)X=E=>X=((I-D)^(-1))E

I =

     1     0     0
     0     1     0
     0     0     1


X =

   1.0e+04 *

    2.7500
    3.3750
    2.4750


X =

   1.0e+04 *

    2.7500
    3.3750
    2.4750