Wikipedia:Reference desk/Archives/Mathematics/2008 April 10

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April 10

LaTeX "compromise"

Is there a way of rendering \displaystyle in LaTeX such that it is slightly smaller, just as in a superscript or subscript?

e.g.

$e^{This\,\sum _{n}^{looks}asty\,with\,subscripts_{n}}$

$e^{This\,\displaystyle \sum _{b}^{looks}etter\,but\,is\,too\,large_{b}}$

x42bn6 Talk Mess 19:35, 10 April 2008 (UTC)

If you are concerned about the final subscript of a superscript:

$e^{This\,\sum _{better}^{looks}\,what\,do\,you\,think?_{\scriptstyle {n}}}$

$e^{This\,\sum _{nasty}^{looks}\,just\,like\,the\,original_{\scriptscriptstyle {n}}}$

If you are concerned about the later text of the superscript:

$e^{This\,\displaystyle \sum _{better}^{looks}\,\scriptstyle {what\,do\,you\,think?}_{b}}$

And don't forget \mathrm, \mathit, \mbox and their kin:

$e^{\mathrm {This} \,\displaystyle \sum _{\mathit {best}}^{\mathit {looks}}\,\scriptstyle {\mathit {what\,do\,you\,think\!?}}_{b}}$

Baccyak4H (Yak!) 02:22, 11 April 2008 (UTC)

Thanks, I'll take a look at those solutions. I was looking for a "shrunk" version of \displaystyle but couldn't find one. x42bn6 Talk Mess 23:15, 11 April 2008 (UTC)

Simplifying factorial equations

What software exists to help simplify equations involving large factorials? NeonMerlin 21:48, 10 April 2008 (UTC)

Any mathematical software should be able to handle factorials. Try Mathematica or Maple (or many others, but those are the two I know a little about). --Tango (talk) 22:39, 10 April 2008 (UTC)

Or SAGE, which is free, includes and unifies other pre-existing free mathematical software (among which GAP computer algebra system) and can use functions and packages from Mathematica, Maple etc., if you have them. Then again, perhaps this is a bit of an overkill just to simplify some factorials. Goochelaar (talk) 08:12, 11 April 2008 (UTC)

It will help if you give an example of what you have in mind. -- Meni Rosenfeld (talk) 09:43, 11 April 2008 (UTC)

Depending on what you're doing, you may be able to use the Gamma function or Stirling's approximation to simplify things (perhaps even reduce things to pencil & paper territory). -- 128.104.112.85 (talk) 18:01, 11 April 2008 (UTC)

Algebra

How do you solve

 4sinx0 +1 = -2

• ^^**^**^^*^*^*^**^22:12, 10 April 2008 (UTC)172.141.191.133 (talk)

DOVENSTONE

I assume you mean find x such that $4\sin x+1=-2$. Just rearrange the equation until you have $\sin x=a$ where a is some constant, and then take inverse sin of both sides. -mattbuck (Talk) 22:21, 10 April 2008 (UTC)

4sinx + 1 = -2 Isolate x or for now sinx so subtract 1 and divide by 4. Sinx = -3/4 then take the sin inverse of -3/4 I don't have a calculator with me but I'm sure you can do that so you should get x= #. I'm pretty sure that should be it

Draw a circle with center at B=(0,0) and radius 4. Let A=(4,0). Draw a horizontal line through the point (0,-3) meeting the circle at a point C on the left of y-axis. Then the angle ABC is your x. Using a compass, you can get an approximate value. I never use any powerful calculator in my life. twma 13:00, 16 April 2008 (UTC)