Question 1182572
.
<pre>

This map is the reflection of a coordinate plane about x-axis.


The kernel is 0 (zero; zero vector).


The range is the entire R^2, i.e. whole coordinate plane.



The fact that it is linear map is OBVIUOS; but you can check it formally on your own, 

if you know the definition of a linear map.
</pre>

----------


Read your textbook.


Or you write your own, instead of reading the existing textbooks ?




By the way, what university are you and what is your Algebra textbook ?