From 0667eb894ed2f2c2448d88606c125420092a08b0 Mon Sep 17 00:00:00 2001 From: Drew Lewis Date: Tue, 12 May 2026 17:07:12 +0000 Subject: [PATCH 1/2] Section 5.1 --- source/linear-algebra/source/05-GT/01.ptx | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/source/linear-algebra/source/05-GT/01.ptx b/source/linear-algebra/source/05-GT/01.ptx index b6fd2316c..cb62fec92 100644 --- a/source/linear-algebra/source/05-GT/01.ptx +++ b/source/linear-algebra/source/05-GT/01.ptx @@ -158,7 +158,7 @@ What is the area of the transformed unit square? B\vec e_1=\left[\begin{array}{cc} 2 & 3 \\ 0 & 4 \end{array}\right]\left[\begin{array}{c}1\\0\end{array}\right] =\left[\begin{array}{c}2\\0\end{array}\right]=2\vec e_1 - + \def\arraystretch{1.25} B\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right] = \left[\begin{array}{cc} 2 & 3 \\ 0 & 4 \end{array}\right]\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right] @@ -175,7 +175,7 @@ What is the area of the transformed unit square? \draw[thin,gray,<->] (-4,0)-- (4,0); \draw[thin,gray,<->] (0,-4)-- (0,4); \draw[thick,blue,->] (0,0) -- node[below] {\(B\left[\begin{array}{c}1\\0\end{array}\right]=2\left[\begin{array}{c}1\\0\end{array}\right]\)}++ (2,0); - \draw[thick,blue,->] (0,0) -- ++(3,2) node[above] {\(B\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]=4\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]\)}; + \draw[thick,blue,->] (0,0) -- ++(3,2) node[above] {\(\def\arraystretch{1.25} B\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]=4\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]\)}; \draw[thick,red,->] (0,0) -- (1,0); \draw[thick,red,->] (0,0) -- (0.75,0.5); \draw[red,dashed] (1,0) -- (1.75,0.5) -- (0.75,0.5); @@ -228,7 +228,7 @@ What is the area of the transformed unit square? \draw[thin,gray,<->] (-4,0)-- (4,0); \draw[thin,gray,<->] (0,-4)-- (0,4); \draw[thick,blue,->] (0,0) -- node[below] {\(B\left[\begin{array}{c}1\\0\end{array}\right]=2\left[\begin{array}{c}1\\0\end{array}\right]\)}++ (2,0); - \draw[thick,blue,->] (0,0) -- ++(3,2) node[above] {\(B\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]=4\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]\)}; + \draw[thick,blue,->] (0,0) -- ++(3,2) node[above] {\(\def\arraystretch{1.25} B\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]=4\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]\)}; \draw[thick,red,->] (0,0) -- (1,0); \draw[thick,red,->] (0,0) -- (0.75,0.5); \draw[red,dashed] (1,0) -- (1.75,0.5) -- (0.75,0.5); @@ -275,7 +275,7 @@ In order to figure out how to compute it, we first figure out the properties it \draw[thin,gray,<->] (-4,0)-- (4,0); \draw[thin,gray,<->] (0,-4)-- (0,4); \draw[thick,blue,->] (0,0) -- node[below] {\(B\left[\begin{array}{c}1\\0\end{array}\right]=2\left[\begin{array}{c}1\\0\end{array}\right]\)}++ (2,0); - \draw[thick,blue,->] (0,0) -- ++(3,2) node[above] {\(B\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]=4\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]\)}; + \draw[thick,blue,->] (0,0) -- ++(3,2) node[above] {\(\def\arraystretch{1.25} B\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]=4\left[\begin{array}{c}\frac{3}{4}\\\frac{1}{2}\end{array}\right]\)}; \draw[thick,red,->] (0,0) -- (1,0); \draw[thick,red,->] (0,0) -- (0.75,0.5); \draw[red,dashed] (1,0) -- (1.75,0.5) -- (0.75,0.5); @@ -301,7 +301,7 @@ If \det([\vec{e}_1\hspace{0.5em} \vec{e}_2])=\det(I) is the area of resulting parallelogram, what is the value of \det([\vec{e}_1\hspace{0.5em} \vec{e}_2])=\det(I)?

- + \begin{tikzpicture} \fill[red!50!white] (0,0) rectangle (1,1); From 7b0062354c0a21fca21390375c87ae460be60b63 Mon Sep 17 00:00:00 2001 From: Drew Lewis Date: Tue, 12 May 2026 17:07:41 +0000 Subject: [PATCH 2/2] Typo --- source/linear-algebra/source/05-GT/03.ptx | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/source/linear-algebra/source/05-GT/03.ptx b/source/linear-algebra/source/05-GT/03.ptx index 1a06ceea5..f56ed8187 100644 --- a/source/linear-algebra/source/05-GT/03.ptx +++ b/source/linear-algebra/source/05-GT/03.ptx @@ -15,7 +15,7 @@

- Let R\colon\IR^2\to\IR^2 be the transformation given by rotating vectors about the origin through and angle of 45^\circ, and let S\colon\IR^2\to\IR^2 denote the transformation that reflects vectors about the line x_1=x_2. + Let R\colon\IR^2\to\IR^2 be the transformation given by rotating vectors about the origin through an angle of 45^\circ, and let S\colon\IR^2\to\IR^2 denote the transformation that reflects vectors about the line x_1=x_2.