double integral
- To: mathgroup at smc.vnet.net
- Subject: [mg34173] double integral
- From: "Higinio Ramos" <higra at usal.es>
- Date: Wed, 8 May 2002 01:57:41 -0400 (EDT)
- Reply-to: "Higinio Ramos" <higra at usal.es>
- Sender: owner-wri-mathgroup at wolfram.com
Why does Integrate fail in solving the double integral?
In[1]:=Integrate[x^2,{y,0,Sqrt[6]},{x,y,6/y}]
Out[1]= -9
Of course, If I do the evaluations in two steps, the result is
correct:(the integral does not converge)
In[3]:=
2 6
Integrate[x , {x, y, -}]
y
Out[3]=
3
72 y
-- - --
3 3
y
In[4]:=
3
72 y
Integrate[-- - --, {y, 0, Sqrt[6]}]
3 3
y
\!\(Integrate::"idiv" : "Integral of \!\(72\/y\^3 - y\^3\/3\) does not
converge on \!\({0, \\@6}\)."\)
Out[4]=
3
72 y
Integrate[-- - --, {y, 0, Sqrt[6]}]
3 3
y