A <linear map> is one-to-one, or <injective>, when equal outputs imply equal inputs. Equivalently its <kernel> is $\{0\}$: subtracting inputs converts equality of outputs to a zero output. Here \b[$T$ is not one-to-one], since its kernel has dimension two. Concretely, $T(-2,-1,1,0)=T(0)=0$ for distinct inputs.

Solution

Past exam of the year 1 of the computer science course of the University of Oxford / 2018 / Digital systems, linear algebra, introduction to formal proof / 5 / c / iv / Solution

 Solution (source code)