Using $u_1=(1,1,1,1),u_2=(0,1,1,1),u_3=(0,0,1,1),u_4=(0,0,0,1)$ create an arbitrary vector $(a_1,a_2,a_3,a_4)\in \mathbb{R}^4$ as a linear combination
40619
How to write down a vector as a linear combination of other 4 vectors?
123220
Quick doubt about multiplying vectors by scalars
6398
Can the product of an $4\times 3$ matrix and a $3\times 4$ matrix be invertible?
9143
Solve $u_{xx}-3u_{xt}-4u_{tt}=0$ where $u(x,0)=x^2$ and $u_t(x,0)=e^x$
60571
Interweaving vectors
83449
Proof with 3D vectors
33944
Describe $\mathbb{R}[x]/(x^{2}+ax+b)$ where $a,b \in \mathbb{R}$
59598
The vectors are orthonormal
103230
Find the general solution of $4u_{xx}+5u_{xy}+u_{yy}+u_x+u_y=2$
52973
The identity $(u\times v)\cdot(x\times y)=\begin{vmatrix}u\cdot x&v\cdot x\\ u\cdot y&v\cdot y\\\end{vmatrix}$
84806
Generate all possible combinations of the elements of some vectors (Cartesian product)
74187
$\operatorname{ord}(u)=r,\,\operatorname{ord}(v)=s$ $\,\Rightarrow\,\operatorname{ord}(uv)=rs\,$ if $\,r,s\,$ (co)primes
76510
vector identity for triple scalar product
146300
Fast way to create $[ I_4\otimes e_1,\ \dots ,\ I_4 \otimes e_T]$?
37794
Proving the two given vectors are orthogonal
4240
The proof of Triple Vector Products
154735
$so(4)=su(2)× su(2)$