Determine the fourth roots of -16 in the form $x +iy$ where $x$ and $y$ are not trigonometric functions. I do not even know what they really want from me ...

I've just begun to re-learn linear algebra because is so important, the book that I chose is naturally the Hoffman's for a lot of reason. Well, ...

I can't find this result anywhere, but it seems pretty straightforward. I want to avoid silly mistakes, but I can't see any fault. I'd love...

If we have to valid integrating factors to a differential equation we must get the same general solution using each of them although we get two new equati...

I have a cone (vertex at $(x,y,z)=0$) with height $H$ and radius $a$ (radius of the base). Here is a picture: I want to find the moment of inertia around ...

I dont understand this definition of finite elements: The triple $(K,P,\Sigma)$ with $K \subset \mathbb{R}^n$ connected lipschitz domain with non-empty in...

Let $G$ be a group and $a\in Z(G)$, where $$ Z(G) =\lbrace x \in G\mid xg=gx~~ \forall g\in G\}.$$ Prove that $H=\langle a\rangle$ is a normal subgroup of...

I am trying to work out the percentage difference between two numbers (one of which is negative), NOT PERCENTAGE CHANGE. I have done quite a bit of readin...

Why 6 % 10 = 6 As fa as I know 10 % 6 = 4, but I don't know how to handle the first one Thanks!

From what I understand, a k-form in the real numbers is essentially a mapping $\mathbb{R^k} \rightarrow \mathbb{R}$, but I can't seem to find a corre...