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Doug, copying from your site,

df/dt = (∂f/∂x)(dx/dt) + (∂f/∂y)(dy/dt) + (∂f/∂z)(dz/dt)

that is relatively sort on paper is actually a mouthful when spoken. You
might also recall your professor speaking it as follows, nearly turning blue
at the end:

dee-f dee-t *equals* the partial of f with respect to x, times dee-x dee-t *
plus* the partial of f with respect to y, times dee-y dee-t *plus* the
partial of f with respect to z, times dee-z dee-t

That is actually an abbreviated form already, because the more complete way
to say it would be:

the derivative of f with respect to t *equals* the partial derivative of f
with respect to x, times the derivative of x with respect to t *plus* the
partial derivative of f with respect to y, times the derivative of y with
respect to t *plus* the partial derivative of f with respect to z, times the
derivative of z with respect to t

df/dt = (∂f/∂x)(dx/dt) + (∂f/∂y)(dy/dt) + (∂f/∂z)(dz/dt)

Something closer to the full spoken form you have above could be
dft = ∂fx*dxt + ∂fy*dyt + ∂fz*dzt,
which doesn't have (or need) all the redundant d's and ∂'s.

stevo

On Sat, Jun 12, 2010 at 5:17 PM, Douglas Treadwell <[log in to unmask]
> wrote:

> Gary, even then though it's a lot of syllables.  There's got to be a way to
> shorten it.  I came up with something you can see at
> www.dougtreadwell.com/calculish.htm.  Let me know what you think.
>
> - Doug
>
>
>
>
> ________________________________
> From: Gary Shannon <[log in to unmask]>
> To: [log in to unmask]
> Sent: Mon, June 7, 2010 9:09:54 PM
> Subject: Re: Improved Language for Mathematics
>
> As a retired engineer, it seems to me that once you understand what
> "dee ex, dee tee" means it would be no more cumbersome than any other
> collection of sounds we might utter. For me it was more the concept of
> limits as dt->0 than the way a symbol is read that was the real
> challenge.
>
> Once I learned to "speak math", myself and my fellow engineers had no
> trouble at all "conversing" in math. As for the second derivative,
> where I worked at least we tended to say "dee-two-ex, dee-two-tee",
> not altogether dissimilar to "are-two-dee-two" or "see-three-pee-oh".
>
> --gary
>
> On Mon, Jun 7, 2010 at 8:59 PM, Douglas Treadwell
> <[log in to unmask]> wrote:
> > Anyone here have any ideas about better ways of verbalizing calculus
> equations?  For example dx/dt is normally said as "the derivative of x with
> respect to t" or "dee ex, dee tee", but both are cumbersome.  It gets even
> worse when you have d^2x/d^2t, "the second derivative of x with respect to
> t" or "dee squared ex, dee squared tee", etc.  I'm interested in any
> suggestions you might have.
> >
> > - Doug
> >
>