Factoring a constant from each row of matrix

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Factoring a constant from each row of a matrix affects its determinant, which is linear in both rows and columns. When a factor of 2 is taken from each row of the given matrix, it results in a multiplication of the determinant by 2 for each row, leading to a total factor of 16. This is because 2 raised to the power of the number of rows (4) equals 16. To maintain the determinant's value after dividing a row by 2, the entire determinant must be multiplied by 2. Therefore, the determinant reflects this adjustment, resulting in the factor of 16.
Derill03
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Why is it that a 16 comes out when you factor a 2 from each row of this matrix:

0 2 2 2
2 0 2 2
2 2 0 2
2 2 2 0
 
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Because 2*2*2*2 is 16 (one for each row). Determinants are linear in both columns and rows, so if you divide a column by 2, the determinant also becomes half as much as it was before. If you want to keep the value of the determinant the same, you have to multiply it by 2. So when you divide the first row by 2 to make it (0, 1, 1, 1), you have to multiply the whole thing by 2.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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