left-hand derivative

left-hand derivative

[′left ‚hand də′riv·əd·iv]
(mathematics)
The limit of the difference quotient [ƒ(x) - ƒ(c)]/[x-c ] as x approaches c from the left, that is, x <>c only.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.