# Homework Help: How do Mathmeticians Pronounce This?

1. Nov 29, 2008

How do Mathematicians pronounce the ellipsis? (...) for instance:

1 + 2 + 3 + ... + an

"One plus two plus three plus dot dot dot plus a sub n"?

I'm using a digital tape recorder to better understand text, and I don't want to pronounce this incorrectly.

Also: do mathematicians say "the arc tangent of one" or "the inverse tangent of one"?

2. Nov 29, 2008

### mgb_phys

"and so on"
I would say arc-tan but that's from a software background

3. Nov 29, 2008

Got it, thanks ^^

4. Nov 29, 2008

### Office_Shredder

Staff Emeritus
I usually say "sumfrom k equals one to 'n' of [whatever the kth term is in terms of k]" and get rid of the ellipsis entirely

or sometimes even

"sigma from k equals one to 'n' of [whatever the kth term is in terms of k]"

And I would say "arctan of one" also, or sometimes "tangent to the minus one of one" but that's a bit unwieldy

When I'm looking at a complicated expression and just want to get the notation right.

5. Nov 29, 2008

It is actually very interesting to hear how other people put a mathematical expression into words: it kind of forces you to define what it is you are talking about beyond just symbols and numbers.

On a side note, my professor had a wonderful time laughing when I said "you-ler" instead of "oil-er" for Euler's number.

6. Nov 30, 2008

### kidmode01

One of my old professors got a good laugh when people pronounced the 's' in l'Hospital's rule. It seems the more common spelling is l'Hôpital's. Another one of my professors told me the 's' wasn't always silent. Can anyone confirm that?

7. Nov 30, 2008

My professor pronounces it "leh-pee-tal's rule" or "pee-tal's rule".

8. Nov 30, 2008

### robphy

Check out the audio examples from the AsTeR project:
http://www.cs.cornell.edu/home/raman/aster/aster-toplevel.html

9. Dec 1, 2008

### cristo

Staff Emeritus
Nope, you're professor is wrong. Just think about it: it's a person's name, so it should sound the same regardless of how it's spelt. The s is silent and arises when replacing the circumflex.