Obtain the general solution of the different equation $$\frac{d^2y}{dx^2}-3\frac{dy}{dx}+2y=20\sin x.$$ Hence find the particular solution for which : $y=...

If $R$ is a ring, J is an ideal in $R$, and $I$ is an ideal of $J$ (with $J$ considered as a ring), does it follow that $I$ is an ideal of $R$? That is, i...

I'm trying to help my daughter with her math homework and after scouring google and websites I find I truly do not understand how to complete this ev...

Recently, when asking for the derivative of angular momentum, I gave my own solution $$ \frac {d \vec L} {dt} = \frac {d \vec r_{(t1)}} {dt} \times \frac ...

Let $X$ and $Y$ be independent, normally distributed random variables. How is $|X| + |Y|$ distributed? Is it known to be $|Z|$, where $Z$ is distributed n...

I do not seem to understand the logic behind choosing the correct integration bounds and integration order when dealing with spherical coordinates. For ex...

The standard logarithm expansion is given by \begin{equation} \log(1-x) = -\sum_{n=1}^{\infty}\frac{x^n}{n}, \qquad |x|<1 \end{equation} I have a sum w...

Say I have a vector $\mathbf{\theta} = (1,2,3)'$. I'm looking for a way to write the number of components/coordinates in the vector. Something l...

Do zero sum games have a pure Nash equilibrium and if so how do I find the pure Nash equilibrium

Check whether the series is convergent? $\sum_{n=1}^{\infty}\frac{1}{\sqrt{n}}\tan(\frac{1}{n})$