Search Results
Search type | Search syntax |
---|---|
Tags | [tag] |
Exact | "words here" |
Author |
user:1234 user:me (yours) |
Score |
score:3 (3+) score:0 (none) |
Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
Views | views:250 |
Code | code:"if (foo != bar)" |
Sections |
title:apples body:"apples oranges" |
URL | url:"*.example.com" |
Saves | in:saves |
Status |
closed:yes duplicate:no migrated:no wiki:no |
Types |
is:question is:answer |
Exclude |
-[tag] -apples |
For more details on advanced search visit our help page |
2
votes
Accepted
Finite difference approximation
Given pairwise distinct real numbers $x_0,\dots,x_4$, one can approximate $f'(x_0)$ by a linear combination $a_0f(x_0)+\cdots+a_4f(x_4)$ so that
$$g_j'(x_0)=a_0g_j(x_0)+\cdots+a_4g_j(x_4)$$
for $g_j(x …
2
votes
Change of variable formulas in discrete calculus?
$\newcommand\De\Delta$Elementarily: The relation $f=\De_h^{-1}g$ means that $f(x+h)-f(x)=g(x)$ for all $x$.
For a function $g$ and each real $r$, we know $f_r:=\De_1^{-1}g_r$, where $g_r(x):=g(rx)$, s …