$I(X\times Y)=I(X)+I(Y)$ for affine varieties $X$ and $Y$?
86034
Is it true that for algebraic sets $V,W$ we have $I(V \times W ) =I(V) + I(W)$?
126561
Proof of equivalence of algebraic and geometric dot product?
64656
how do you prove that $A\times (B\setminus C) = (A\times B) \setminus (A\times C)$?
120642
Let $g : \Bbb N \times \Bbb N \to\Bbb N \times \Bbb N$ defined as $g(m,n) = (m + n,m - n)$
80684
Counter example for $(A \times B) \cap (C \times D) = (A \cap C ) \times (B \cap D)$
80916
How to prove that if $A\subseteq A\times A$, then $A=\varnothing$?
40490
Birational isomorphism $\mathbb{P}^n\times \mathbb{P}^m\to \mathbb{P}^{n+m}$
47670
Algebraic proof of $\sum_{i=0}^k{{n \choose i}{m \choose {k-i}}}= {{m+n}\choose k}$
118727
$g(x+y)+g(x)g(y)=g(xy)+g(x)+g(y)$ for all $x,y$.
152104
How do I prove that $ij = k?$
154754
Is $O_n$ isomorphic to $SO_n \times \{\pm I\}$?
26302
Prove that $(X \cap Y) \cup Z = (X \cup Z) \cap (Y \cup Z)$
112707
Must $Q^\mathsf{T}Q = I$ if $(Qx)^\mathsf{T}(Qx) = x^\mathsf{T}x$
121995
Hilbert's Nullstellensatz implies $I(Z(I)) = \sqrt{I}$
20612
Is fibre product of varieties irreducible (integral)?
156443
if $x$ and $y$ commute with $[x y]$, then $[x y]$ is nilpotent
155828
How do I show that $A$ and $A^T$ are similar, given that the minimal polynomial of $A$ splits over $\mathbb{F}$?