Linear algebra determinant of linear operator

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The discussion focuses on proving that the determinant of a linear operator T, when adjusted by a scalar λ and an identity operator I, remains consistent across different ordered bases of a finite-dimensional vector space V. It establishes that det(T - λI) is equal to det([T]β - λI), where [T]β is the matrix representation of T with respect to the basis β. The conversation highlights the importance of understanding the notation and the implications of changing bases, as this affects the matrix representation of the linear transformation. It also clarifies that the coordinates of vectors change with the basis, necessitating adjustments in the corresponding matrices. Overall, the thread emphasizes the relationship between linear transformations, their matrix representations, and determinants across different bases.
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[SOLVED] linear algebra determinant of linear operator

Homework Statement



Let T be a linear operator on a finite-dimensional vector space V.
Define the determinant of T as: det(T)=det([T]β) where β is any ordered basis for V.

Prove that for any scalar λ and any ordered basis β for V that det(T - λIv) = det([T]β - λI).

Homework Equations



Another part of the problem yielded that for any two ordered bases of V, β and γ , that det([T]β) = det([T]γ).


The Attempt at a Solution



I need someone to help me understand the notation. I don't actually know what I am being asked to prove here.
 
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T is the general linear transformation. [T] is the matrix that represents the linear transformation with respect to the basis B. If we change the basis, then we change the matrix since if TX = Y where X and Y are the coordinate vectors in K^n representing the abstract vectors x,y in V. (We can do with since any n dimensional vector space is isomorphic to K^n.) These coordinates are just the coefficients of the basis vectors.
ie:if x = a1v1 +a2v2 + .. + anvn where v1 ...vn is a basis then the coordinate vector for x just (a1,a2,a3,...,an). Obviously these coordinates change when the basis changes. The same holds for Y which means our matrix will need to change to reflect this.

Also, X and Y are column vectors so that the matrix multiplication is defined.
 
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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