From 6d0262c89fee04495ab37785f22f58609bf192c6 Mon Sep 17 00:00:00 2001
From: Andrew Lorimer <andrew@lorimer.id.au>
Date: Mon, 20 Aug 2018 12:46:16 +1000
Subject: [PATCH] linear gradients ez

---
 methods/calculus.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/methods/calculus.md b/methods/calculus.md
index 589bf2f..8cb3521 100644
--- a/methods/calculus.md
+++ b/methods/calculus.md
@@ -18,8 +18,12 @@
 
 ## Average rate of change
 
+$$m \operatorname{of} x \in [a,b] = {{f(b)-f(a)}\over {b - a}} = {dy \over dx}$$
+
 Average rate of change between $x=[a,b]$ given two points $P(a, f(a))$ and $Q(b, f(b))$ is the gradient $m$ of line $\overleftrightarrow{PQ}$
 
+On CAS: (Action|Interactive) -> Calculation -> Diff -> $f(x)$ or $y=\dots$
+
 ## Instantaneous rate of change
 Tangent to a curve at a point - has same slope as graph at this point.
 Values for $\Delta$ are always approximations.
-- 
2.49.0