How do you find a missing column of a composed matrix from the columns of the second matrix?
Conditions
- A is a linear transformation represented by a matrix.
- Columns are read as vectors in the domain of A.
Reasoning, step by step
- Identify the index j of the missing column in .
- Extract the j-th column from matrix B.
- Compute the product of matrix A and this column vector.
- The resulting vector is the j-th column of .
Example
In the video, the middle column of is missing. The middle column of B is . Applying A to this vector gives , which fills the blank spot.
Common misconceptions
- Trying to transform the columns of A instead of B.
- Assuming the missing column can be found by simple arithmetic on other columns without applying the transformation.
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