From c707a6eb28c341a60151c53cb5fa7ba559a2439e Mon Sep 17 00:00:00 2001 From: ben-jaynes <1btjaynes@gmail.com> Date: Thu, 28 May 2026 00:10:37 -0700 Subject: [PATCH] vault backup: 2026-05-28 00:10:37 --- Wiki/Math/Determinite of a Matrix.md | 0 Wiki/Math/Vector Basics.md | 25 ++++++++++++++++++++----- 2 files changed, 20 insertions(+), 5 deletions(-) create mode 100644 Wiki/Math/Determinite of a Matrix.md diff --git a/Wiki/Math/Determinite of a Matrix.md b/Wiki/Math/Determinite of a Matrix.md new file mode 100644 index 0000000..e69de29 diff --git a/Wiki/Math/Vector Basics.md b/Wiki/Math/Vector Basics.md index 52b86f0..35a044d 100644 --- a/Wiki/Math/Vector Basics.md +++ b/Wiki/Math/Vector Basics.md @@ -1,13 +1,23 @@ #rs/class/math163 #math - - - ## Operations -### Projection -$$proj_{u}v=\frac{u\cdot v}{\left|\left|u\right|\right|^{2}}u$$ -Used to project vector $v$ onto $u$ -![[VectorProjection.excalidraw]] + +### Addition +$$\vec{u} + \vec{v} = $$ + +### Subtraction +$$\vec{u} - \vec{v} = $$ + +### Dot Product +$$\vec{u} \cdot \vec{v} = $$ + +### Magnitude +$$||\vec{u}|| = \sqrt{ u_{1}^2 + u_{2}^2}$$ + ### Unit Vector -$$ unit_u=\frac{u}{||u||}$$ +$$ unit_u=\frac{\vec{u}}{||\vec{u}||}$$ Used to find the vector of magnitude 1 in the same direction as $u$ + ### Cross Product $$a \times b = \begin{vmatrix} i&j&k\\a_1&a_2&a_3\\b_1&b_2&b_3\end{vmatrix}= i(a_2b_3-a_3b_2)-j(a_1b_3-a_3b_1)+k(a_1b_2-a_2b_1)$$ Used to create a vector that is orthogonal to both $a$ and $b$. To find what direction it will point in use the right-hand rule (thumb, pointer and middle finger). @@ -18,6 +28,11 @@ Properties: - On self $$ a \times a = 0 $$ The magnitude of the cross product of two vectors can be found with $$||u \times v|| = ||u|| * ||v|| * \sin(\theta)$$ The magnitude of the cross product is equal to the area of the parallelogram formed with two adjacent sides as the vectors. + +### Projection +$$proj_{u}v=\frac{u\cdot v}{\left|\left|u\right|\right|^{2}}u$$ +Used to project vector $v$ onto $u$ +![[VectorProjection.excalidraw]] ### Triple Scalar Product Find the Determinant of: $$u * (v \times w) = \begin{vmatrix} u_{1} && u_{2} && u_{3} \\ u_{1} && u_{2} && u_{3} \\ u_{1} && u_{2} && u_{3} \end{vmatrix}$$