Help finding error in my Circuit Analysis

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SUMMARY

The discussion focuses on troubleshooting errors in circuit analysis calculations using LT Spice. The user initially calculated current values i1, i2, and i3 as -0.005179, -0.002857, and 0.004857, respectively, which differed significantly from the LT Spice simulation results of 0.00059081, 0.000809628, and 0.00119037. Key errors identified included using an incorrect resistor value in the matrix and mislabeling terms in the super mesh equation. After correcting these mistakes, the user successfully aligned their results with the LT Spice output.

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mkematt96
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Homework Statement


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Homework Equations

The Attempt at a Solution


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My values for i1,i2,and i3 were: -.005179,-.002857 and .004857. When I ran the same circuit through LT Spice the values they gave me were .00059081,.000809628, and .00119037. Where did I make my error?
* as a side not I notices I only have 1000 instead of 10,000 in my matrix for the first line. The values I got were using 10,000 instead of 1000 in the first line.
 

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Since you know the answer from your simulation result, I'd post the values I am getting.
I am getting VAB= 7.221V and IR3= 1.4mA.

For I1, I2 and I3 (labelled differently in my working) I am getting the same values as your LTspice result (just 10 times more, since you used 10000 instead of 1000).
 
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I see a couple of mistakes. In your equation for loop 1 you left out the 5k resistor.

In your equation for the super mesh, you have a term 4k(I1 - I2). This should be 4k(I2 - I1).
 
The Electrician said:
I see a couple of mistakes. In your equation for loop 1 you left out the 5k resistor.

In your equation for the super mesh, you have a term 4k(I1 - I2). This should be 4k(I2 - I1).
After making these changes I got my numbers to match the LT Spice number! Thanks!
 

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