The image below is from my lecture notes for Linear analysis:
Shouldn't it be $T:X\to X$? If not, I have no idea what it means, because if $z$ is in $X$ then there is no reason as to why $x + z$ should be in $Y$.
The image below is from my lecture notes for Linear analysis:
Shouldn't it be $T:X\to X$? If not, I have no idea what it means, because if $z$ is in $X$ then there is no reason as to why $x + z$ should be in $Y$.