From 0441237b200b302ffa2f75a2886c4cacc4d5ac75 Mon Sep 17 00:00:00 2001 From: Pineal Servo Date: Sat, 25 Jan 2014 18:57:08 -0700 Subject: [PATCH] Added matrix examples --- scratch.page | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/scratch.page b/scratch.page index 003c8bb..299bfef 100644 --- a/scratch.page +++ b/scratch.page @@ -41,4 +41,40 @@ This follows from **Bayes' Theorem** which says $$ P(A|B) = \frac{P(B | A)\, P(A)}{P(B)} +$$ + +# Matrix Stuff +This is a column vector: +$$\vec v = \left(\begin{matrix} +1\\ +3\\ +7 +\end{matrix}\right)$$ + +The *vector sum* of $\vec u$ and $\vec v$ is: + +$$\vec u + \vec v = +\left(\begin{matrix} +u_1\\ +\vdots\\ +u_n +\end{matrix}\right) + \left(\begin{matrix} +v_1\\ +\vdots\\ +v_n +\end{matrix}\right) = \left(\begin{matrix} +u_1 + v_1\\ +\vdots\\ +u_n + v_n +\end{matrix}\right) +$$ + +The *scalar multiplication* of the real number $r$ and the vector $\vec v$ is: + +$$ +r \cdot \vec v = r \cdot \left(\begin{matrix} +v_1\\ \vdots \\ v_n +\end{matrix}\right) = \left(\begin{matrix} +rv_1 \\ \vdots \\ rv_n +\end{matrix}\right) $$ \ No newline at end of file