From 372920a4f4b1a274989b0d814392f2d980705de3 Mon Sep 17 00:00:00 2001
From: Andrew Lorimer <andrew@lorimer.id.au>
Date: Mon, 1 Apr 2019 16:29:39 +1100
Subject: [PATCH] [spec] rational functions

---
 spec/calculus.md | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/spec/calculus.md b/spec/calculus.md
index c59c4b7..c9a364e 100644
--- a/spec/calculus.md
+++ b/spec/calculus.md
@@ -257,3 +257,13 @@ $${dy \over dx} = {{dy \over dt} \over {dx \over dt}} \> \vert \> {dx \over dt}
 
 $${d^2 \over dx^2} = {d(y^\prime) \over dx} = {{dy^\prime \over dt} \over {dx \over dt}} \> \vert \> y^\prime = {dy \over dx}$$
 
+# Rational functions
+
+$$f(x) = {P(x) \over Q(x)} \quad \text{where } P, Q \text{ are polynomial functions}$$
+
+## Addition of ordinates
+
+- when two graphs have the same ordinate, $y$-coordinate is double the ordinate
+- when two graphs have opposite ordinates, $y$-coordinate is 0 i.e. ($x$-intercept)
+- when one of the ordinates is 0, the resulting ordinate is equal to the other ordinate
+
-- 
2.43.2