Consider a linear map $A$ on a finite dimensional complex linear space $V$. Its resolvent operator is $R(x)=(x\mathbb{I}-A)^{-1}$. $R(\lambda)$ does not exist if and only if $x=\lambda$ is an eigenvalue of $A$. Now, the problem is to prove that there is some $n\leq \dim V$ such that the limit $$ \lim_{x\to\lambda}(x-\lambda)^n R(x) $$ does exist. Of course this can be done by using the Cramer's rule for the inverse of $(x\mathbb{I}-A)$. However, is it not possible to prove this from the definition of $R(x)$ and without introducing determinants?
2026-02-23 12:07:49.1771848469
Poles of the resolvent of a matrix
235 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in LINEAR-ALGEBRA
- An underdetermined system derived for rotated coordinate system
- How to prove the following equality with matrix norm?
- Alternate basis for a subspace of $\mathcal P_3(\mathbb R)$?
- Why the derivative of $T(\gamma(s))$ is $T$ if this composition is not a linear transformation?
- Why is necessary ask $F$ to be infinite in order to obtain: $ f(v)=0$ for all $ f\in V^* \implies v=0 $
- I don't understand this $\left(\left[T\right]^B_C\right)^{-1}=\left[T^{-1}\right]^C_B$
- Summation in subsets
- $C=AB-BA$. If $CA=AC$, then $C$ is not invertible.
- Basis of span in $R^4$
- Prove if A is regular skew symmetric, I+A is regular (with obstacles)
Related Questions in SPECTRAL-THEORY
- Why is $\lambda\mapsto(\lambda\textbf{1}-T)^{-1}$ analytic on $\rho(T)$?
- Power spectrum of field over an arbitrarily-shaped country
- Calculating spectrum and resolvent set of a linear operator (General question).
- Operator with compact resolvent
- bounded below operator/ Kato-Rellich
- Show directly that if $E_1\geqslant E_2\geqslant\dots$, then $E_i\rightarrow \bigwedge E_i$ strongly.
- Is the spectral radius less than $1$?
- How to show range of a projection is an eigenspace.
- Spectral radius inequality for non-abelian Banach algebras
- Do unitarily equivalent operators have the same spectrum?
Related Questions in FUNCTIONAL-CALCULUS
- About vectors that have bounded support representation on the spectrum of a self-adjoint operator
- proving existence of a particular linear operator on the space of bounded functions
- How do I prove that the following function is increasing in $t\geq 1$ for any $1\leq y \leq t$?
- Proving that a family of exponential operators has a uniform bound, without semigroup theory.
- Consider the operator $T:L^2(0,1)\rightarrow L^2(0,1)$. Is it well defined, linear, bounded, compact?
- Is this a Functional Differential Equation? How to solve it?
- Holomorphic functional calculus proving a property of fractional powers
- Showing that the Holomorphic Functional Calculus preserves adjoints.
- Compute $\frac{d}{dx(t)}\int_0^Tx(\tau)^TAx(\tau)d\tau$
- If $f \in C(\sigma(a))$ and $g \in C(\sigma(f(a)))$, proof that $(g \circ f)(a) = g(f(a))$
Trending Questions
- Induction on the number of equations
- How to convince a math teacher of this simple and obvious fact?
- Find $E[XY|Y+Z=1 ]$
- Refuting the Anti-Cantor Cranks
- What are imaginary numbers?
- Determine the adjoint of $\tilde Q(x)$ for $\tilde Q(x)u:=(Qu)(x)$ where $Q:U→L^2(Ω,ℝ^d$ is a Hilbert-Schmidt operator and $U$ is a Hilbert space
- Why does this innovative method of subtraction from a third grader always work?
- How do we know that the number $1$ is not equal to the number $-1$?
- What are the Implications of having VΩ as a model for a theory?
- Defining a Galois Field based on primitive element versus polynomial?
- Can't find the relationship between two columns of numbers. Please Help
- Is computer science a branch of mathematics?
- Is there a bijection of $\mathbb{R}^n$ with itself such that the forward map is connected but the inverse is not?
- Identification of a quadrilateral as a trapezoid, rectangle, or square
- Generator of inertia group in function field extension
Popular # Hahtags
second-order-logic
numerical-methods
puzzle
logic
probability
number-theory
winding-number
real-analysis
integration
calculus
complex-analysis
sequences-and-series
proof-writing
set-theory
functions
homotopy-theory
elementary-number-theory
ordinary-differential-equations
circles
derivatives
game-theory
definite-integrals
elementary-set-theory
limits
multivariable-calculus
geometry
algebraic-number-theory
proof-verification
partial-derivative
algebra-precalculus
Popular Questions
- What is the integral of 1/x?
- How many squares actually ARE in this picture? Is this a trick question with no right answer?
- Is a matrix multiplied with its transpose something special?
- What is the difference between independent and mutually exclusive events?
- Visually stunning math concepts which are easy to explain
- taylor series of $\ln(1+x)$?
- How to tell if a set of vectors spans a space?
- Calculus question taking derivative to find horizontal tangent line
- How to determine if a function is one-to-one?
- Determine if vectors are linearly independent
- What does it mean to have a determinant equal to zero?
- Is this Batman equation for real?
- How to find perpendicular vector to another vector?
- How to find mean and median from histogram
- How many sides does a circle have?