# Tagged Questions

Questions on (ordinary) differential equations. For questions specifically concerning partial differential equations, use the (pde) tag.

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### Can I apply Hartman-Grobman when only one eigenvalue is zero?

Consider $\begin{bmatrix} \dot x\\ \dot y \end{bmatrix} =\begin{bmatrix} xy^2 -xy\\ x-y \end{bmatrix}$. If we take the Jacobian and evaluate it at $(0,0)$, one of the eigenvalues is $-1$ and the other ...
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### Which of the following equations must be true?

$$C =\frac{5}{9} (F - 32)$$ The equations above shows how temprature $F$, measured in degrees fahrenheit, relates to a temprature $C$, measured in degrees Celcius. Based on the equation, which of the ...
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### Solution to $\frac{d^2f}{dr^2}+\frac{1}{r}\frac{df}{d r}=0$

I know that $f(r)=aln(r)+b$ where $a$ and $b$ are constants is a solution of $$\frac{d^2f}{dr^2}+\frac{1}{r}\frac{d f}{dr}=0$$ are there any other solutions to this, would appreciate it if someone ...
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### Initial Value Problem using Laplace transformation: What is the ${\cal L}$ transform of $u(t-5)$?

I'm solving past exam questions in preparation for an Applied Mathematics course. I came to the following exercise, which poses a single difficulty. If it's any indication of difficulty, the exercise ...
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