You are watching: D^2y/dx^2 meaning

Because it's the application of the differentiation operator d/dx twice to the function y:

(d/dx)(d/dx)y = (d/dx)2y = (d2/dx2)y = d2y/dx2.

This is an abuse of notation, because of course d/dx is not a fraction of two quantities, but the reason that Leibniz's notation is useful is because viewing the derivative as a fraction (even though it's not) actually suggests true facts, such as the chain rule:

dy/dx = (dy/du)(du/dx)

https://en.wikipedia.org/wiki/Leibniz%27s_notation

12
Share
ReportSaveFollow
level 2
Comment deleted by user · 8 yr. ago

level 1
· 8 yr. ago

2
Share
ReportSaveFollow
level 1
Comment removed by moderator · 8 yr. ago
level 2
· 8 yr. ago
New User

Might I just say, this comment has made me laugh more than anything I've read all week. Just the mental image of Gottfried Leibniz smoking weed and saying "yo duuude check out this it's like, infinitesimals an shit"

1
Share
ReportSaveFollow

r/learnmath
Post all of your math-learning resources here. Questions, no matter how basic, will be answered (to the best ability of the online subscribers).
241k
Members

195

Online

Created Nov 29, 2009
Join

Top posts february 22nd 2014Top posts of february, 2014Top posts 2014