Engineering Board Exam Reviewer · Matrix Inverse and Cofactors · hard

Find the cofactor C12 of the matrix bmatrix1&2&3\4&5&6\7&8&10 bmatrix.

1. 2
2. -2
3. -10
4. 10

Answer

A. 2

Solution

Removing row 1 and column 2 gives the minor vmatrix4&6\7&10 vmatrix=40-42=-2. C12=(-1)1+2(-2)=2.

More Matrix Inverse and Cofactors questions

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