- Description has changed:

Diff:

--- old +++ new @@ -7,9 +7,18 @@ Lisp implementation type: GNU Common Lisp (GCL) Lisp implementation version: GCL 2.6.8 +~~~~ (assume(a>0),integrate(integrate(exp(-a*r+%i*k*r*w)*r^2,w,-1,1),r,0,inf)) +~~~~ says integral is divergent and obviously it is NOT. Upper limit is obviously 0 +~~~~ (t:integrate(exp(-a*r+%i*k*r*w)*r^2,w,-1,1),ratsimp(subst(r=0,integrate(t,r)))) -gives -4*a/(k^4+2*a^2*k^2+a^4) +~~~~ + +gives + +~~~~ +-4*a/(k^4+2*a^2*k^2+a^4) +~~~~