exercise in commutative algebra
27766
Comaximal ideals in a commutative ring
32772
Proving units in a ring
39201
Atiyah-Macdonald, Exercise 5.4
63541
Projective and injective modules; direct sums and products
65873
A proof for Atiyah-Macdonald Exercise I.21.iii
118781
product of ideals in matrix ring
92962
Rings with $a^5=a$ are commutative
16945
Finding the Ideals of a Direct Product of Rings
5893
On the commutative property of multiplication (domain of integers, possibly reals)
118911
Classifying Unital Commutative Rings of Order $p^2$
79535
Prove that $R$ is a commutative ring if $x^3=x$
79650
Division Rings and Division Algebras
114662
Construction of a specific non-commutative and infinite group (with conditions on the order of the elements)
70394
Prove that $a * b$ is a group (Hungerford, 2nd ed., sec $7.2$, Exercise $22$)
133878
Ring of order $p^2$ is commutative.
142612
Matrix Ring of a Semisimple Ring
57732
Rings of fractions and homomorphisms