diff --git a/College/AU 26/MATH 208 (Matrix Algebra)/Chapter 2.1 Notes.md b/College/AU 26/MATH 208 (Matrix Algebra)/Chapter 2.1 Notes.md index ad1d85e..36d7d13 100644 --- a/College/AU 26/MATH 208 (Matrix Algebra)/Chapter 2.1 Notes.md +++ b/College/AU 26/MATH 208 (Matrix Algebra)/Chapter 2.1 Notes.md @@ -1,7 +1,34 @@ #uw/notes #uw/class/math208 - - - -Vectors can be represented vertically in a matrix: -$$u = \begin{bmatrix} +Vectors can be represented vertically in a matrix (column vector): +$$\mathbf{u} = \begin{bmatrix} u_{1} \\ u_{2} \\ \vdots \\ u_{n} \end{bmatrix}$$ + +> [!NOTE] Basic Properties +> if + +if $\mathbf{u}$ and $\mathbf{v}$ are vectors defined as +$$\mathbf{u} =\begin{bmatrix} +u_{1} \\ u_{2} \\ \vdots \\ u_{n} +\end{bmatrix} \quad \text{and} \quad \mathbf{v} =\begin{bmatrix} +v_{1} \\ v_{2} \\ \vdots \\ v_{n} +\end{bmatrix}$$ + +**Equality:** +$\mathbf{u}=\mathbf{v}$ if and only if $u_{1}=v_{1}, u_{2}=v_{2},\dots,u_{n}=v_{n}$ +**Addition:** +$$\mathbf{u}+\mathbf{v} = \begin{bmatrix} +u_{1} \\ u_{2} \\ \vdots \\ u_{n} +\end{bmatrix} + \begin{bmatrix} +v_{1} \\ v_{2} \\ \vdots \\ v_{n} +\end{bmatrix} = \begin{bmatrix} +u_{1}+v_{1} \\ u_{2}+v_{2} \\ \vdots \\ u_{n}+v_{n} +\end{bmatrix}$$ +**Scalar Multiplication:** +$$c \mathbf{u} = c \begin{bmatrix} +u_{1} \\ u_{2} \\ \vdots \\ u_{n} +\end{bmatrix} = \begin{bmatrix} +c \cdot u_{1} \\ c \cdot u_{2} \\ \vdots \\ c \cdot u_{n} +\end{bmatrix}$$