Mathematica the Simplify[] command

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Homework Statement


Simplify to a certain extent, as much as possible (factorized form would be best):

[tex]\frac{\sqrt{3}}{2}\left(\frac{md}{m-\sqrt{3}}\right)^2+\frac{\sqrt{3}}{2}\left(\frac{m(s+d)}{m+\sqrt{3}}\right)^2+\frac{1}{2}\left(s+\frac{md}{m-\sqrt{3}}-\frac{m(s+d)}{m+\sqrt{3}}\right)\left(\frac{\sqrt{3}md}{\sqrt{3}-m}+\frac{\sqrt{3}m(s+d)}{m+\sqrt{3}}\right)[/tex]


The Attempt at a Solution


This isn't an actual question but rather a part of a bigger picture. I need this simplified as much as possible before I can even think of manipulating it further.

I've tried quite a bit, but after expanding the last factored expression, it became pretty ugly. This route seems most promising:

[tex]\frac{\sqrt{3}}{2}\left(\left(\frac{md}{m-\sqrt{3}}\right)^2+\left(\frac{m(s+d)}{m+\sqrt{3}}\right)^2+\left(s+\frac{md}{m-\sqrt{3}}-\frac{m(s+d)}{m+\sqrt{3}}\right)\left(\frac{m(s+d)}{m+\sqrt{3}}-\frac{md}{m-\sqrt{3}}\right)\right)[/tex]

[tex]\frac{\sqrt{3}}{2}\left(\left(\frac{md}{m-\sqrt{3}}\right)^2+\left(\frac{m(s+d)}{m+\sqrt{3}}\right)^2+s\left(\frac{m(s+d)}{m+\sqrt{3}}-\frac{md}{m-\sqrt{3}}\right)-\left(\frac{2\sqrt{3}md+\sqrt{3}ms-m^2s}{m^2-3}\right)^2\right)[/tex]

[tex]\frac{\sqrt{3}}{2}\left(\left(\frac{md}{m-\sqrt{3}}\right)^2+\left(\frac{m(s+d)}{m+\sqrt{3}}\right)^2-s\left(\frac{2\sqrt{3}d+\sqrt{3}s-ms}{m^2-3}\right)-m^2\left(\frac{2\sqrt{3}d+\sqrt{3}s-ms}{m^2-3}\right)^2\right)[/tex]

I'm unsure of what else to do without making a big mess. And this still isn't simple enough for what I need this for, so if you have the stomach to tackle this, please do so :smile:
 


Long algebraic expression with fractions involving m, d, s and square roots of 3, equated to a simplified fraction with numerator -6dm - 3s^2 + 2sqrt(3)d^2m + sqrt(3)ms^2 + 2sqrt(3)dms over (m - sqrt(3))(m + sqrt(3)).
 
Attachments
  • Long algebraic expression with fractions involving m, d, s and square roots of 3, set equal to a simplified fraction (-6ds - 3s^2 + 2 sqrt3 d^2 m + sqrt3 m s^2 + 2 sqrt3 d m s) over (m - sqrt3)(m + sqrt3), multiplied by m/2.
    factor.jpg
    9.9 KB · Views: 501


Thanks for the response.

I don't quite understand what your final solution is. When it gets to the : and then it has just one entire fraction. That one fraction can't possibly be equal? It only has a second degree for m, while if you look at this part which is located on the last line in the last factor of my OP:

[tex]m^2\left(\frac{2\sqrt{3}d+\sqrt{3}s-ms}{m^2-3}\right)^2[/tex]

it clearly suggests the denominator should be of a 4th degree in m, no?
 


I hope this answers your question.(=
Typeset algebra showing a long symbolic expression with fractions and square roots, transforming one side into a simplified polynomial over a rational expression, continued across several lines with equals signs.
 
Attachments
  • Typeset algebra showing a long symbolic expression simplified step by step, with fractions containing square roots and polynomial terms in m, d, s, equated to a final polynomial over 2m^4-12m^2+18.
    sol.jpg
    19 KB · Views: 471


Oh wow thanks a lot for that!

It still took me a while to understand what was happening, but it all sunk in :smile: and when I tested it for some values of s,d and m and they turned out equal, I was even more ecstatic!
 


Did you simplify this yourself, or did you use a program of some sort?
Reason being because I'm going to need more simplifying of this type to be done.
 


I've checked with a program and indeed it is the simplest form.
 


If you have access to Mathematica the Simplify[] command would come in handy.

Come to think of it there might also be something similar you can use on Wolfram Alpha to simplify expressions.