Determinant of Skew-Symmetric Matrix: Is it Zero for Odd n?

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A skew-symmetric matrix A satisfies the condition AT = -A, leading to the property that det(A) = det(-A). For an odd-dimensional matrix (n is odd), it follows that det(-A) = -det(A), which implies that 2det(A) = 0, thus concluding that det(A) must be zero. The discussion raises the question of whether this property holds for even n, but the focus remains on proving the zero determinant for odd n. The relationship between the determinant and the odd dimension is crucial in establishing this conclusion. Therefore, the determinant of a skew-symmetric matrix is zero when n is odd.
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Homework Statement



A square (nn) matrix is called skew-symmetric (or antisymmetric) if AT =
-A. Prove that if A is skew-symmetric and n is odd, then detA = 0. Is this true
for even n?

Homework Equations


Det(A) = Det(AT) where AT= the transpose of matrix A


The Attempt at a Solution


I started to try and say that since AT=-A then Det(AT) = Det(-A) so Det(A) = Det(-A) b/c the law that Det(A)=Det(AT) but I didnt know where to go from here.. specifically what impact does the odd number of n have to do with anything.. Any help
 
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and I assume that I need to say that Det(-A) = -Det(A) for the odd number on n so then I could conclude 2Det(A)=0 but i don't see why: Det(-A) = -Det(A) is true for odd number n matrices
 
You can easily calculate det(-I), no?? (where I is the identity matrix)
Then you can write det(-A)= det((-I)A).
 
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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