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How do I invert and verify a mathematical matrix?
Please show me step-by-step how to Invert the following matrix
A = [7 4]
[5 3]
and verify the solution by showing that AA-1 = I2.
Thank you
1 Answer
- Anonymous1 decade agoFavourite answer
Invert the matrix by augmenting with with the identity matrix and taking it to reduced row echelon form (make the identity matrix appear in the left half of the new matrix). For example:
7 4 1 0
5 3 0 1
Should become:
1 0 x y
0 1 a b
The right half of the last matrix (x,y;a,b) is your inverse. Then just matrix-multiply to show that its the 2x2 identity matrix (I2)