I'm trying to find the Covariance of $X$ and $Y$. I see that the $Cov(X,Y) = E[XY] - E[X]E[Y]$. I know how to find the expectation of single variable...

My Problem: x mod(3) = 2 x mod(5) = 4 x mod(7) = 1 Solve for x I was given a formula x = (x mod(3) * 70 + x mod(5) * 21 + x mod(7) * 15) mod(105) to solve...

Consider this function and its horizontal asymptote. Can the asymptote (in blue) also be considered a tangent line to the curve (in red)? The slope of the...

For a simple summation: $$ Z = \sum_{x=1}^X x^n $$ Solve for n. I have googled unsuccessfully and I do not remember this.

While experimenting with integrals involving the Dedekind Eta function, I came across a family of integrals which seem to follow a very simple pattern. Wi...

I have been reading this topic about scaled partial pivoting. And I'm not able to figure out some things like when should we use scaled partial pivot...

Let's say you have a group of eight people and you want to form them into pairs for group projects. There are $\frac{8!}{4! 2^4}$ ways to do it. ($8!...

Two questions Let $R$ be commutative and have $1_R$. Two ideals are called coprime/comaxmal if $I + J = R$ (1) the above is equivalent to saying there exi...

I am little bit confused about the sign " | ". Some people call it the division sign and some call it "such that". In computer programming, it's know...

First I had the simple notion that the trignometric ratios are ratios of sides of a triangle. But when $\sin(0) = 0 , \cos(0) = 1 $ what do they mean? I h...