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1 vote
1 answer
87 views

Evaluate $\lim_{j \rightarrow +\infty} (I + A/j)^j$

Let $A$ be a $n\times n$ matrix. Evaluate $$ \lim_{j \rightarrow +\infty} \left(I + \frac{A}{j}\right)^j. $$ My guess is $e^A$. My attept: \begin{align*} \lim_{j \rightarrow +\infty} (I + \frac{...
Luísa Borsato's user avatar
0 votes
3 answers
121 views

Exponentiation of a $2\times 2$ matrix

We know: $$\exp(At)=I+ \sum^{\infty}_{n=1}\frac{A^nt^n}{n!}$$ Here $$A= \begin{pmatrix} 0 & 1 \\ -w^2 & 0\end{pmatrix}$$ is a $2\times 2$ matrix, $I$ is identity matrix. How to show: $$\...
104078's user avatar
  • 1,919
0 votes
2 answers
78 views

Let $A$ be a single $p\times p$ Jordan block. Find general solution to $\dfrac{dx}{dt} = Ax$

Let $A$ be a single $p\times p$ Jordan block. Find the general solution to $\,\dfrac{dx}{dt} = Ax$. What should I approach first? Please help!
shimura's user avatar
  • 117
8 votes
4 answers
7k views

How to compute time ordered Exponential?

So say you have a matrix dependent on a variable t: $A(t)$ How do you compute $e^{A(t)}$ ? It seems Sylvester's formula, my standard method of computing matrix exponentials can't be applied here ...
Sidharth Ghoshal's user avatar