Basically my mathematica can’t simplify a simple expression,
DVP can be simplified to sqrt(amh) , which is what I would expect mathematica would give me, (I tried the other functions as well, ‘‘Cancel’’, ‘‘Expand’’,etc), but I just get the same solution that doesn’t look simplified at all,
help me plz :D.
Here’s what I get when giving some assumptions. Otherwise Mathematica must give results which are generally valid.
In[1]:= dvp = Sqrt[(Sqrt[(a m)/h^5] Sqrt[a h m])/h];
In[2]:= Simplify[dvp]
Out[2]= Sqrt[(a m Sqrt[(a m)/h^5])/Sqrt[a h m]]
In[3]:= Simplify[dvp, Assumptions -> Element[_, Reals]]
Out[3]= Sqrt[a m]/Abs[h]^(3/2)
In[4]:= Simplify[dvp, Assumptions -> {Element[_, Reals], h > 0}]
Out[4]= Sqrt[(a m)/h^3]
Dear Tigran,
I think that the problem is that the expression does not simplify the way you think it simplifies without making additional assumptions. You need to consider cases when the variables are negative or complex numbers etc.
I suppose that something similar to what you want happens when you make for example the following assumptions:
Simplify[Sqrt[(Sqrt[(a m)/h^5] Sqrt[a h m])/h], Assumptions -> {a > 0, m > 0, h > 0}]
That gives
This is different from what you expect, but I think that you might have made a mistake there in your calculation. An alternative set of assumptions could be:
Simplify[Sqrt[(Sqrt[(a m)/h^5] Sqrt[a h m])/h], Assumptions -> {a \[Element] Reals, m \[Element] Reals, h \[Element] Reals}]
or equivalently
Simplify[Sqrt[(Sqrt[(a m)/h^5] Sqrt[a h m])/h], Assumptions -> {{a, m, h} \[Element] Reals}]
both of which give
Hope this helps,
M.
Hi David,
sorry, your reply came in just before mine… I had not seen it before submitting.
Cheers,
M.
Hi Marco,
In this case, more is better. And I think your reply is more informative.
Kind regards, David
Thx guys, using assumptions worked 