Transformations and Vectors covers translation, reflection, rotation and enlargement, and column vectors.
Translation, reflection and rotation keep the shape the same size; enlargement changes the size by a scale factor. The magnitude of a column vector $\begin{pmatrix}a\\b\end{pmatrix}$ is $\sqrt{a^2+b^2}$, so $\begin{pmatrix}3\\4\end{pmatrix}$ has magnitude 5.
Remember
- Enlargement changes size; the others keep it the same.
- Vector magnitude $= \sqrt{a^2+b^2}$.