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I'm calculating an integral,

Integrate[(t e^(-z t) e^(-q t))/(1-e^(-t)), t],

and the result is

ConditionalExpression[Zeta[2, Global`z + Global`q], Re[Global`z + Global`q] > 0].

I do not understand the meaning of Global`z and Global`q, and I'll appreciate your explanation.

J. M.'s missing motivation
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N.S.
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    Global is the global name space. This is where things that has no specific name space lives in. Basically when you define a variable, it goes by default to the global name space (called context in Mathematica). You can force variable to go into named context using the Begin[contextName]... command. btw, Did you mean e to be Exp ? Start again from clean kernel. What do you get now? – Nasser May 20 '22 at 09:06
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    Clear[e,q,z]. – cvgmt May 20 '22 at 09:19
  • Thanks @Nasser , yes, e denotes Euler's number, and that works. I tried again in a new notebook and the Global is gone. – N.S. May 20 '22 at 09:19
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    In general lowercase characters don't have built-in meaning, what makes them good for your own variables. But even better, is to not have to use variables at all and keep a clean kernel. See about prevention here. Also do not confuse the related but different constant E with the function Exp. – rhermans May 20 '22 at 09:27

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