Raul Miller wrote: > On 2/26/07, Devon McCormick <[EMAIL PROTECTED]> wrote: >> Where is this "mathematical standard-notation" defined? > > I like the example mentioned in the Gerald Sussman presentation > June Kim recently referenced. > http://www.jsoftware.com/pipermail/general/2007-February/029052.html > > Here's an attempt at presenting that example using ascii (I'm > assuming you're viewing this with a fixed width font): > > 2 > cos x is (cos x)*(cos x) > > but > > -1 > cos x is not 1/(cos x) > >
This is a problem in elementary math courses, By the way, a similar non-inverse stumbling block is the convention of writing cos x^2 to mean cos(x^2). The exponent -1 to indicate an inverse function was introduced by Herschel in 1813. Inverse cosine at this time was commonly written (1/cos) y or ang. (Cos = y). And, of course, cos y did not mean the same thing as it does today: y was in degrees. Best wishes, John ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
