37
$\begingroup$

My current research colleague from New Castle told me that I was reading it wrong. I usually read it as e power x.

How do you read aloud $e ^ x$?

Is it:

  • e raised to x
  • e power x
  • e powered x
  • or e raised to the power x.

What is the correct pronunciation?

  • 3
    "$e$ raised to the power $x$" is right, and probably most other locutions are just abbreviations of that one. I don't think any of them are good nomenclature. There's no good way to do it.2012-09-23
  • 55
    I've only heard 'e to the x' when that notation is used. $\exp(x)$ would be the exponential of x.2012-09-23
  • 0
    I also read it `e power x`. I am interested to know what correction your colleague gave.2012-09-23
  • 3
    A related terminological problem is that my students all want to describe $x^2$ as "exponential." Whenever they do this, I immediately write down $2^x$ and tell them that it's only exponential if $x$ is in the exponent; $x^2$ is a power law, not an exponential. But this doesn't seem to sink in too well with my students, and it will probably never penetrate popular culture, since "exponential" sounds catchy and cool. Is there any alternative to "power law" that is catchy and has some hope of entering the zeitgeist? "Monomial" seems about as cool as Grandma's cotton panties.2012-09-23
  • 0
    To address some of the terms the answers seem to ignore, "e power(ed) x" is something I have never heard, so it is at least highly nonstandard. I consider "e to the x" best ("raised" can be used in there too).2012-09-23
  • 2
    Grammar nazis? In real life? Would never had suspected it. Anyway, I generally avoid talking about math without a pen and paper, or a whiteboard; that way everybody understood even if you mispronounced x + 2 as "eks bi tu".2012-09-23
  • 7
    Tell him that it's an E to the X, to the A, to the M, to the P, to the L, to the E, and that he shouldn't be bothered by your rapping wit when you describe math. Honestly though, both will be the same to 99% of people.2012-09-23
  • 1
    Newcastle? $y \, i$2012-09-23
  • 0
    I say something like "eatada-x"2012-09-24
  • 0
    I would vote that this question is off-topic for this site. Perhaps it would fit better at the [English.SE](http://english.stackexchange.com) one.2012-09-24
  • 0
    In portuguese: *e elevado a x* --> *e* raised to *x*2012-09-24
  • 0
    To me "e power x" (or the parallel "x power 5" for $x^5$) is something I hear from non-native English speakers, but not ever from natives.2013-01-09
  • 0
    "e raised to x" is how I say it.2013-07-15
  • 0
    I say -ex- as in x... It seems fair.2014-05-21

11 Answers 11

59

I think "e to the x" or "the exponential of x" are both fine. I might even use "e of x."

  • 7
    "e to the x" is the equivalent used in italian "e alla x"2012-09-23
  • 25
    "e-to-the-x" is very common, and is easily enunciated, while some of the other logically-reasonable possibilities are less easily said out loud, I think.2012-09-23
  • 55
    I interpet "e of x" as $e(x)$2012-09-23
  • 2
    @Belgi: Yes, so do I. And I sometimes use $e(x)$ to mean the exponential, to keep things inline. I also have used $e_n(x) = e^{\pi i x / 2n}$ a lot too, but when discussing this with others might still call it "e to the x." Maybe this is just a number theory thing - I blame Gauss. ;p2012-09-23
  • 9
    So at least for once, German is less verbose than English: "$e$ hoch $x$" :)2012-09-23
  • 5
    @enzotib: same in Spanish:: "e a la x"2012-09-23
  • 3
    In French we would only say “Exponentielle de x” or “e exposant x”. When it is all about natural numbers we also use the form “10 puissance 9”.2012-09-24
41

When I read it out loud, I prefer saying e to the $\rm x$ because it is a quick phrase and means the same as e raised to the $x$th power. Albeit, it still differs from person-to-person.

12

I would usually say "e to the x", but when the interpretation is clear "e x" is sufficient to me.

  • 10
    I never say “ee eks”, and I have never heard anyone say that.2012-09-24
  • 0
    Perhaps not in the first explanation of an equation, but if you have to say it many times, that's what I default to. Particularly reading/taking about anything in continuous time finance, $e^{-rT}$ quickly becomes 'ee minus arr tee' for me.2012-09-24
  • 0
    in french "e x" is used quite often. or at least, was, 3~4 years ago when I was on college (on the condition that e is not a variable in this context)2012-09-25
  • 0
    I have too got accustomed to e x. +12014-03-14
10

I always read it as "e to the power of x", which is perhaps a little verbose.

  • 2
    Same here. I find that this is as succinct as I can be without stepping over the line of ambiguity. It is what I say as a shortening of "e *raised* to the power of x".2012-09-24
8

Given that your avatar is the infamous Wolfram|Alpha logo "hombic hexecontahedron", I suppose you're reasonably familiar with Mathematica. If you have Mathematica handy, there is a systematic solution to this type of questions, viz. how to pronounce some mathematical expressions in Engish, using Mathematica's SpokenString[] function. For example,

In[19]:= SpokenString[e^x]

Out[19]= "e to the power of x"

Some more complex expressions such as $\int_0^1 \sin (x) dx$ which is written in Mathematica as Integrate[Sin[x], x, {x, 0, 1}] can evaluate by itself, and hence need to be wrapped with HoldForm and then passed to SpokenString[]:

In[21]:= SpokenString[HoldForm[Integrate[Sin[x], x, {x, 0, 1}]]]

Out[21]= "the integral of sine of x over x from 0 to 1, then with respect to x"

In[22]:= SpokenString[Integrate[Sin[x], x, {x, 0, 1}]]

Out[22]= "x minus x times cosine of 1"

I've heard that this (combined with Speak[]) is used to aid teaching blind and/or deaf people mathematics.

5

We usually say; e to the power x (e is supposed to be raised and its value will increase )

  • 4
    I think saying that "its value will increase" is a little misleading.2012-10-11
5

e to the x is what I say. I think that as long as it's understood what you mean, it's OK.

5

I say, "e to the x." It is simplest.

5

e raised to the power x

is correct and clear

to the students what you mean

  • 13
    With such line breaks, I / was expecting an artful / haiku, but alas.2012-09-24
  • 2
    I made it a haiku2012-11-23
3

Since no one else (except the OP) has suggested this: even though mostly I would say "$e$ to the $x$", I often say "$e$ raised to the power $x$".

1

i think "exponential of $x$" is the correct way but "e to the x" is also used commonly