Proving a lemma on decomposition of V to T-cyclic subspace

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SUMMARY

The discussion centers on a lemma regarding the decomposition of a vector space V into T-cyclic subspaces, specifically when T is a linear operator with a minimal polynomial of the form f(t)^n, where f(t) is a monic irreducible polynomial. The lemma states that V can be expressed as a direct sum of T-cyclic subspaces Z(v_i, T) with corresponding T-annihilators f(t)^{n_i}. Participants express frustration over the lack of clarity in the proof provided in Schaum's outlines linear algebra, particularly the absence of detailed explanations between conclusions. A suggestion is made to first prove the lemma for the case where n=1, simplifying the proof process.

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  • Understanding of linear operators and vector spaces
  • Familiarity with minimal polynomials and their properties
  • Knowledge of T-cyclic subspaces and T-annihilators
  • Basic proof techniques in linear algebra
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  • Study the proof of the lemma for the case where n=1
  • Review the properties of monic irreducible polynomials in linear algebra
  • Explore the concept of T-cyclic subspaces in greater detail
  • Examine examples of vector space decompositions in linear algebra
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Students of linear algebra, mathematicians focusing on operator theory, and anyone seeking to deepen their understanding of vector space decompositions and T-cyclic subspaces.

Adgorn
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I am reading Schaum's outlines linear algebra, and have reached an explanation of the following lemma:
Let ##T:V→V## be a linear operator whose minimal polynomial is ##f(t)^n## where ##f(t)## is a monic irreducible polynomial. Then V is the direct sum
##V=Z(v_1,T)⊕...⊕Z(v_r,T)##
of T-cyclic subspaces ##Z(v_i,T)## with corresponding T-annihilators
##f(t)^{n_1}, f(t)^{n_2},..., f(t)^{n_r}, n=n_1≥n_2≥...≥n_r##
Any other decomposition of V into T-cyclic subspaces has the same number of components and the same set of T-annihilators.

Now, it seems that while writing the explanation for this lemma the writer forgot the concept of explaining one's arguments when presenting a proof, which resulted in a long explanation which goes from one conclusion to the next without explaining how, which naturally was rather frustrating. If anyone could present the proof for this lemma to me, I would be very grateful.
Should you require it I can also copy the proof from the book (page 343 problem 10.31).
Thanks in advance to all the helpers.
 
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Try proving it first for the case ##n=1## so that the minimal polynomial is irreducible.
 

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