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Good morning,

I have this strange problem. I have to divide a product of 5 variables by 4 of the 5 variables : $C x_1 * x_2* x_3 *x_4 / (x_1 * x_2* x_3 *x_4)$. Now if I do this I don't obtain only $C$ but $C x_3/x_3$. Also with Refine or FullSimplify doesn't change. Now pay attention: if I try with the code written in the way you should read if I would paste it :

A = C*Product[Subscript[x, 
    i], {i, 1, 4}]/(Subscript[x, 1]*Subscript[x, 2]*Subscript[x, 3]*
     Subscript[x, 4])

I obtain 

C

I put a photo to summarize (excuse me but my laptop has some problems with screenshot).

Why???? How we could do in the first method?

code_photo

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    $\begingroup$ go to the right of the expression C x_3/x_3 and type // FullForm . Most likely x_3 in the numerator is not the same as x_3 in the numerator but they look the same when typeset. $\endgroup$
    – kglr
    Oct 6, 2018 at 15:40
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    $\begingroup$ TIP: 1) don't use subscripts. 2) Don't use upper-case variables. $\endgroup$
    – AccidentalFourierTransform
    Oct 6, 2018 at 15:50
  • $\begingroup$ @kglr ok but it gives an expression Times[C,Subscript[x,3],Power[Subscript[x,TextCell["3"]],-1]] ( i have reported the expression because if i paste it add some other stuff). Now how can i have A= C ? $\endgroup$
    – siderius
    Oct 6, 2018 at 15:50
  • $\begingroup$ @AccidentalFourierTransform i cant because i have to work with productory and many variables whose index is related to other things $\endgroup$
    – siderius
    Oct 6, 2018 at 15:52
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    $\begingroup$ there you have it: Subscript[x,3] is obviously not the same as Subscript[x,TextCell["3"]] $\endgroup$
    – kglr
    Oct 6, 2018 at 15:52

1 Answer 1

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Screen capture of replicating the issue and solution:

enter image description here

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