Real 1 not equal to complex 1
60775
Why are integers subset of reals?
86015
$\mathbb Q[x]/(x^2+1)$ is not isomorphic to $\mathbb Q[x]/(x^2+2)$
93888
What do we lose passing from the reals to the complex numbers?
139168
Prove that there is an unique $z$ s.t. $f(z) = z$ where $z$ is a complex number
147986
Prove: if $|z|=1$ than $\frac{z+1}{z-1}$ is an imaginary number
95145
Does $\exp(2ir\pi)$ equal $1$? What's wrong?
114822
Prove or disprove an inequality involving complex numbers
106940
Why are complex numbers considered to be numbers?
107076
Prove $S^1$ is not homeomorphic to $S^2$ using connectedness
134575
Show that the mapping $f → f~'$ from $C^1([0 , 1])$ to $C([0 , 1])$ is not continuous.
38674
Do complex numbers really exist?
96363
How to show that $\mathbb R^n$ with the $1$-norm is not isometric to $\mathbb R^n$ with the infinity norm for $n>2$?
142076
$c$ is a complex number that satisyfing $(c+\frac{1}{c}+1)(c+\frac{1}{c}) = 1$
118903
The sup norm on $C[0,1]$ is not equivalent to another one, induced by some inner product
59239
For non-zero real $x$, $y$, $z$ and complex $a$, $b$, $c$ with $|a|=|b|=|c|$, if $x+y+z=0=ax+by+cz$, then $a=b=c$
149529
Name for complex number with nonzero imaginary component
108633
Why $f^{-1}(f(A)) \not= A$