# Strange thing about simplification between product and productory [closed]

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?

• 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.
– kglr
Oct 6 '18 at 15:40
• TIP: 1) don't use subscripts. 2) Don't use upper-case variables. Oct 6 '18 at 15:50
• @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 ? Oct 6 '18 at 15:50
• @AccidentalFourierTransform i cant because i have to work with productory and many variables whose index is related to other things Oct 6 '18 at 15:52
• there you have it: Subscript[x,3] is obviously not the same as Subscript[x,TextCell["3"]]
– kglr
Oct 6 '18 at 15:52