For some [[../02 Areas/Math/Linear Transformation|Linear Map]] $T$:
Suppose that $T$ is [[../02 Areas/Math/Injective|one-to-one]],
$ \begin{align}
\let x \neq y &\in \R^n \\
T(\vec x) - T(\vec y) &= T(\vec x - \vec y) \neq \vec 0 \\
\vec x - \vec y &\neq \vec{0} \\
T(\vec x) &\neq T(\vec y)
\end{align} $