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Assume v. Presume

Just to spoil the argument (sigh), language is a matter of convention, and convention defines the difference between square metres and metres square that does not necessarily apply when expressing other quantities (such as acceleration, where "metres per second per second" expresses the concept of acceleration far better than "metres per square second").
 
Black Hole said:
Just to spoil the argument (sigh), language is a matter of convention, and convention defines the difference between square metres and metres square that does not necessarily apply when expressing other quantities (such as acceleration, where "metres per second per second" expresses the concept of acceleration far better than "metres per square second").
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That's "metres per second squared!" It's maths, which is also a language. The units are metres/(seconds squared). To see this, change from metres to kilometres, or from seconds to minutes, and that bit of maths tells you by how much the numbers have to be changed. The latter changes the numbers by a factor of 60 x 60.
 
Mike0001 said:
In Windoze, there is Character Map, but there is a paucity of powers there. In fact, you can't do anything other than ⁰¹²³⁴⁵⁶⁷⁸⁹⁺₀₁₂₃₄₅₆₇₈₉₊₋₌₍₎ which is very limiting. I can't raise anything to power n, for instance, or s to power -2.
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You can get a lot of the Character Map characters by using Alt key plus the numeric keypad (with Num Lock ON). eg: ² is Alt+0178
If you open the Character Map and click a char the keystroke for it, if there is one, is in the bottom right of the window.

But for 'proper' maths you need a specialist app. My daughter had one when she was maths at uni, but it was a pay for it job (and not cheap :( )
 
Black Hole said:
IIRC there is an equation constructor in Word.
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BRILLIANT!

Now why equation and not formula? An equation is something like x=y but x+y is not an equation! Go to the back of the class, Microsoft!

@MikeSh Alt 0178 just converts this tab into a new tab for me! It used to work on old PCs but I guess loads of these Alt codes have been subverted now. Anyway, the characters you can get in Unicode are so limited, there isn't much point.

 
Mike0001 said:
BRILLIANT!
Click to expand...
But apparently not brilliant enough!

Mike0001 said:
Now why equation and not formula? An equation is something like x=y but x+y is not an equation! Go to the back of the class, Microsoft!
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Now that really is being picky! I can't imagine any use for an (for example) integral or sigma sign other than in association with an (real or implied) equality (or other comparison) sign. Even a naked x+y must have an implied equality, even if the equality is stated in text rather than as a symbol.

It seems to me that the likes of H₂SO₄ is a formula, not x+y+z.

(Phew! Back on topic!)
 
Black Hole said:
But apparently not brilliant enough!


Now that really is being picky! I can't imagine any use for an (for example) integral or sigma sign other than in association with an (real or implied) equality (or other comparison) sign. Even a naked x+y must have an implied equality, even if the equality is stated in text rather than as a symbol.

It seems to me that the likes of H₂SO₄ is a formula, not x+y+z.

(Phew! Back on topic!)
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Not picky at all. Formulae appear inline all the time, and rarely are they equations. An equation is a particular type of formula. It's like using the word sentence instead of word. Even an inline variable name is a formula. Something like x automatically goes into italic. There is no implied or otherwise equality in x+y. Or an integral such as $\int_0^\infty x \log x dx$. They are formulae, not equations.
 
Black Hole said:
IIRC there is an equation constructor in Word.
Click to expand...

FWIW, in case anyone is interested, there is also an equation constructor in OpenOffice 3.3 (and presumably Libre Office and Apache OpenOffice 4) as long as you install the relevant package - access via Insert >> Object >> Formula (Mike0001 will be pleased). For iOS users, take a look at the 69p package "TeX Equation".
 
I don't think so. The nearest seems to be - ŷ. I have no idea what that is otherwise.
Why would I need it?
Ye is the accepted way to use it now, although we no longer pronounce it as th.
 
I can think of many instances when I would/could use a diphthong. I have never found the need to type a thong.
Perhaps you can give me an example.
 
Black Hole said:
I agree, because in this case x+y is being used in an entirely abstract way and is not even a formula. Give me a real example of a passage containing a "formula".
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That was one. It doesn't have to be abstract. There is no implication that there has to be equality to something. In fact, the mathematical term may not even allow equality to anything.

There are millions of examples online. This is just one of many. Notice that sometimes the equations are displayed and sometimes they are inline. Conversely, some of the non-equation formulae are displayed, but every single bit of maths in there is a formula, even a single term, like $s_i$ (x subscripted with an i, impossible in Unicode?

http://www.emis.de/classics/Riemann/Grund.pdf

If you look at the source

http://www.emis.de/classics/Riemann/Grund.tex

you will see that the inline formulae are generally preceded and followed by a $, and the displayed ones are surrounded by \[ ...\]. Equations that need alignment of the $=$ sign are displayed within an {eqnarray} environment.

What would be the point of sticking equalities in the table on p293 in Chapter 10 of the following?

http://www.math.odu.edu/~jhh/counter8.html

(Apart from a pointless justification of the argument that all formulae are equations?) (Not that equations even include inequalities by the way!)

Finally, I defy you to justify converting most of the mathematics in the following into equations.

http://www.freebookcentre.net/maths-books-download/gotoweb.php?id=1889
 
I would not use either "equation" or "formula" as terms for something like "x+y". As a mathematician I would call it an "expression". Of course in Word you would need to make the context clear by calling it a "mathematical expression".
 
gomezz said:
I would not use either "equation" or "formula" as terms for something like "x+y". As a mathematician I would call it an "expression". Of course in Word you would need to make the context clear by calling it a "mathematical expression".
Click to expand...

True, I would generally use expression too, as it also covers non-formulaic expressions like $a \mapsto b$, $f:A \to B$ etc.

a ↦ b
f: A → B
 
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