# Tagged Questions

72 views

### Pulling powers to the outside of expressions (inverting PowerExpand)

Is there something like an inverse of PowerExpand that pulls powers to the outside of expressions: $$x^2 y^2 \leadsto (x y)^2 \\ x^2/y^2 \leadsto (x/y)^2$$ I ...
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### Giving hints to Integrate

I working with the integral ...
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### Factoring terms out of a polynomial

I don't do much algebra in Mathematica and was surprised to discover, while attempting to answer this question, that I had no idea how to factor out an expression from a polynomial. The question was, ...
104 views

### Replacement rules in combination with pure functions to make a change of variables

I have defined my function in this way w = f[r,Θ] ; After some calculations i obtained my results with respect to the previous function. For instance: ...
201 views

### How to Make a change of variables

I have the following expresion ...
118 views

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### Replacing composite variables by a single variable

To replace a single variable by another variable, one can simply use the the replace all (/.) operator (e.g., ...