linear gradients ez

diff --git a/methods/calculus.md b/methods/calculus.md
index 589bf2f73a1e98ae0306acbebbc2b55b2de9bffc..8cb35215e73c998d11398ef33a8a1502f916203c 100644 (file)
--- a/methods/calculus.md
+++ b/methods/calculus.md
@@ -18,8 +18,12 @@
 
 ## Average rate of change
 
 
 ## 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 $\overleftrightarrow{PQ}$
 
 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.
 ## 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.