diff --git a/semester3/analysis-ii/analysis-ii-cheat-sheet.pdf b/semester3/analysis-ii/analysis-ii-cheat-sheet.pdf
index 57526b1..9b4aedd 100644
Binary files a/semester3/analysis-ii/analysis-ii-cheat-sheet.pdf and b/semester3/analysis-ii/analysis-ii-cheat-sheet.pdf differ
diff --git a/semester3/analysis-ii/analysis-ii-cheat-sheet.tex b/semester3/analysis-ii/analysis-ii-cheat-sheet.tex
index e14639e..6d99567 100644
--- a/semester3/analysis-ii/analysis-ii-cheat-sheet.tex
+++ b/semester3/analysis-ii/analysis-ii-cheat-sheet.tex
@@ -70,6 +70,7 @@ You could also print it as two A5 pages per A4 page and also print the
 \newsection
 \section{Differential Equations}
 \input{parts/diffeq/00_intro.tex}
+\input{parts/diffeq/linear-ode/00_intro.tex}
 
 
 
diff --git a/semester3/analysis-ii/parts/diffeq/linear-ode/00_intro.tex b/semester3/analysis-ii/parts/diffeq/linear-ode/00_intro.tex
index 1b295b1..c1357f5 100644
--- a/semester3/analysis-ii/parts/diffeq/linear-ode/00_intro.tex
+++ b/semester3/analysis-ii/parts/diffeq/linear-ode/00_intro.tex
@@ -1,2 +1,5 @@
-\newsection
+\newsectionNoPB
 \subsection{Linear Differential Equations}
+\compactdef{Linear differential equation of order $k$}
+$y^{(k)} + a_{k - 1}y^{(k - 1)} + \ldots + a_1 y' + a_0 y = b$, with $a_i$ and $b$ functions in $x$. 
+If $b(x) = 0 \smallhspace \forall x$, \bi{homogeneous}, else \bi{inhomogeneous}