[Analysis] Notes and cleanup

Notes for tangent space computation and green's formula.
Also includes fixes for the pagination as result of additions

semester3/analysis-ii/cheat-sheet-jh/parts/diffeq/00_intro.tex

@@ -5,3 +5,5 @@ $f' - a = 0$ has only solution $f(x) = \int_{x_0}^{x} a(t) \dx t$
 \setcounter{all}{6}
 \shorttheorem Let $F: \R^2 \rightarrow \R$ be a differential function of two variables. Let $x_0 \in \R$ and $y_0 \in \R^2$.
 The Ordinary Differential Equation (ODE) $y' = F(x, y)$ has a unique solution $f$ defined on a ``largest'' interval $I$ that contains $x_0$ such that $y_0 = f(x_0)$
+
+A diffeq is ordinary if it has only one variable and is evaluated at the same point.