Stack Exchange
sign up
|
log in
|
chat
|
meta
|
about
|
faq
Mathematics
Questions
Tags
Tour
Users
Ask Question
Badge
Self-Learner
Answered your own question with score of 3 or more.
Joe earned this badge
nov 13 at 12:39
For what real number $r$ is the set $\left.\left\{\begin{pmatrix}a & b \\ c & d\end{pmatrix}\right| a+b+c+d=r\right\}$ a subspace of $M_2$?
Others with this badge
Mathematics Stack Exchange works best with JavaScript enabled