1,655 reputation
18
bio website fkraiem.org
location France
age
visits member for 11 months
seen 11 hours ago

Dec
13
answered Algorithm for the Hill cipher (finding the inverse of the determinant of a $2 \times 2$ matrix modulo $26$)
Dec
13
comment Every infinite abelian group has at least one element of infinite order?
Oh, yes, silly me, a polynomial has only finitely many non-zero coefficients...
Dec
13
comment Every infinite abelian group has at least one element of infinite order?
And also with achille hui's second example, if the field is $\mathbf{F}_2$. (Of course, every non-identity element has order $2$.)
Dec
12
comment Negative Modulo confusion
19 is certainly not "the (correct) answer". At best it is a correct answer, and at worst not correct. But that depends on what the question is, which you have not stated.
Dec
12
revised show a quotient group is cyclic
Added \langle-\rangle and \gcd.
Dec
12
suggested approved edit on show a quotient group is cyclic
Dec
12
comment show a quotient group is cyclic
Well, the standard way to show that a group is cyclic is to exhibit an element $g$ such that every element of the group is a power (or a multiple if you note additively) of $g$. What could $g$ be here?
Dec
11
comment If $A$ is isomorphic to $B$ and $B$ is a field, then $A$ is a field?
I am not sure how the title of this question relates to its content, which doesn't make much sense...
Dec
11
comment Congruence modulo numbers together
This is the same equation twice?
Dec
11
answered Permutation order
Dec
8
comment Prove this using modular arithmetic
Remember that elements of groups come in pairs of inverses, but some "pairs" have only one element.
Dec
8
comment Chinese Remainder Theorem Finding the Modulo
It happens to all of us. ;)
Dec
8
answered Chinese Remainder Theorem Finding the Modulo
Dec
8
comment congruence, please hepl me solve this
Modulo 9? Just test all possibilities...
Dec
7
comment Why is $x^2=a \pmod{p_1p_2}$ solvable when $x^2=a \pmod {p_i}$ is solvable?
Do you know about the Chinese Remainder Theorem?
Dec
7
comment Computing the quotient group
Have you determined the image of $k$, for starters?
Dec
5
comment Ideals, prime ideals and maximal ideals of the ring $K=\mathbb R[x]/\langle (x^2+1)(x-2)^2\rangle$
It may be worthwhile to remember the canonical bijection between the ideals of $R/I$ and the ideals of $R$ which contain $I$.
Dec
5
comment Intersection of Normal Subgroups is Normal in Subgroup but Not Group - Fraleigh p. 143 14.35
It is true that if both $H$ and $N$ are normal in $G$, then $H\cap N$ is normal in $G$, but here $H$ is not normal in $G$.
Dec
4
comment Finding/Creating a Modern Algebra theorem
What are $G$ and $S$?
Dec
4
comment Prove $\forall a,b \in \mathbb{Z}$, $a^2 -4b - 3 \ne 0$ using proof by contradiction
This "then" is supefluous (to say the least).