How to solve co factor examples explain in simple way

In this video explaining one method co factor method. In this example matrix 3X3 order given and expand it. This is very simple example. The cofactor of a square matrix A is a matrix of the same order obtained by multiplying each element of the matrix by its corresponding cofactor which is defined as the signed minor of the element.
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Please watch: "Simple and easily explain basic properties Scalar product important rules"
• Simple and easily expl...
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