In most geometry courses, we learn that there's no such thing as "SSA Congruence".
33858
In most geometry courses, we learn that there's no such thing as "SSA Congruence".
126927
$\mathbb Q$ is not the direct product of two non-trivial groups.
69611
If $R$ and $S$ are rings then $R \times S$ is never a field
4717
The union of linear subspaces is not necessarily a subspace
36011
Show that the product of two consecutive natural numbers is never a square.
34798
Example of element of double dual that is not an evaluation map
152940
There is no such thing as magnetism?
125604
Proof that $\mathbb{Z}$ has no zero divisors
118577
Fallacious proof involving trigonometry
61373
A normal subgroup that is not a characteristic
146891
Why is $\{\emptyset\} \not = \emptyset$?
59908
Intuitive Explanation why the Fundamental Theorem of Algebra fails for infinite sums
80535
Linear congruence fill in the missing step?
79727
Direct proof of non-flatness
5024
Why do we define quotient groups for normal subgroups only?
105301
Example where a simple correlation coefficient has a sign opposite to that of the corresponding partial correlation coefficient
143394
Why is learning modern algebraic geometry so complicated?