Disjoint cycles in permutations

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The discussion centers on the concept of disjoint cycles in permutations, with specific examples provided for permutations f, g, h, and k. The participant questions whether having three cycles in permutation g is acceptable, concluding that it is indeed valid. The orders of the permutations are calculated using the least common multiple (lcm), yielding orders of 10 for f, 6 for g, 6 for h, and 3 for k. Additionally, the participant demonstrates how to express permutation f as a product of transpositions, identifying it as an odd permutation due to the total of five transpositions. The conversation emphasizes the understanding of cycle notation and its implications in permutation theory.
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Homework Statement



Screen Shot 2016-03-26 at 3.57.24 PM.png

Homework Equations

The Attempt at a Solution

My answers for the disjoint cycles of f,g,h,k are as follows. My question concerns my disjoint cycles for g. Are we allowed to have 3 cycles? I would think "yes" because that just makes sense to me.

for f: ( 1 3 8 4 6) (2 5)
g: (2 6 7) (3 8) (4 5)
h: (1 8 7 3 5 2) (4 6)
k: (1 5 4) (2 3 8)

For orders:

order f: lcm(5, 2) = 10
order g: lcm ( 3, 2) = 6
order h: lcm(6, 2) = 6
order k: lcm(3, 3) = 3
 
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Also, if I wanted to write f as a product of transpositions I would take:
f = (1 3 8 4 6) (2 5)
product of transpositions: (1,3)(3,8)(8,4)(4,6)(2,5)
5 total so odd permutation
 
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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