Calculus:Error log

Did you find something that looks like an error (or possible error) to you? Report the error quickly here (anonymous, does not require login, but you can optionally provide an email ID to be notified of the fix).

We have just started logging errors. On this page, you will find information about all errors that persisted on the site for more than one month on any page. Note: This applies only to errors that were not fixed by December 18, 2011. Errors fixed before then are not being logged on this page.

Page	Error description	Version where it was introduced	Version where it was corrected	Why error? Why not caught? ("I" refers to Vipul)
first derivative test	omitted continuity from "succinct version" (now "short version") of test		May 3, 2012	error in judgment, not so much in fact (because continuity assumption was stated in the longer version)
second derivative test	Didn't state that the point of concern must be a critical point in the "What the test states" section though it was stated in the "What the test is for" section	September 19, 2011	May 2, 2012	didn't review, revisit page
point of local extremum implies critical point	Fact numbers in the Explanation column for the local minimum case were somewhat messed up (although fact numbers in the Facts used column were correct)	October 20, 2011	April 25, 2012 (onte that the error was fixed along with many other changes to the page structure)	copy-paste error from maximum to minimum
first derivative test	had "right" in place of "left" for one of the case rows	September 19, 2011	April 24, 2012	didn't review, revisit page
product rule for partial differentiation	directional derivative instead of gradient at one place, and a bunch of minor typos, missing open parenthesis, use of $\cdot$ for function product at one place (might confuse with dot product), and extraneous statements like "let ${\overline {u}}$ be a unit vector" in definition components where no unit vector was needed.		April 2, 2012	didn't revisit page often enough
partial derivative	Had "x" in place of "y" in one of the derivative descriptions/definitions.	December 17, 2011	April 1, 2012	Didn't revisit page often enough