How do I see that $\mathbb{RP}^4$ and $\mathbb{RP}^6$ do not admit fields of tangent $2$-planes?
13262
$\mathbb{R}P^4$ and $\mathbb{R}P^6$ do not admit fields of tangent $2$-planes
64878
Is this polynomial irreducible in $\mathbb{Q}$?
19754
$\mathbb{R}$ \ $\mathbb{Q}$ and $\mathbb{R}^2\setminus\mathbb{Q}^2$ disconnected?
84148
Why is $\mathbb{R}^2$ not a subspace of $\mathbb{R}^3$?
71102
Subfields of $\mathbb{C}$ which are connected with induced topology
108372
Milne Algebraic Geometry - Remark 3.14 confusion
666
Prove that the upper half plane of Cartesian plane is not an affine variety
35305
Why is $\mathbb{R}^2$ not a subset and /or a subspace of $\mathbb{R}^3$?
153589
Integral basis of an extension of number fields
92599
Prove there generally is no isomorphism between $R[x]/(x^2-a)$ and $R^2$
74663
Is $\mathbb{R}$ an algebraic extension of some proper subfield?
67001
Factorizing polynomials over fields other than $\mathbb{C}$
86234
Explain why $\mathbb{Z \times Z}$ and $\mathbb{R \times R}$ is not a field
147047
Does there exist a polynomial $p(x) \in \mathbb C[x]$ such that $p(x) \notin \mathbb R[x]$ and $p(x)p(-x)=p(x^2)$?
136168
Tangent planes to $2+x^2+y^2$ and that contains the $x$ axis
38911
Squares in $\mathbb{Z}_p$ that are not squares in $\mathbb{Z}$
83919
How to show $D_3\oplus D_4$ is not isomorphic to $D_{24}$?