Hi all,

I am a new use of Maple. I have a expression :

2.560000000*10^(-30)*k1*(2.309486127*10^38*n-1.154743064*10^38-1.186994552*10^37*k2^2*n^2+2.373989104*10^37*k2^2*n+8.541613702*10^37*k2*n^2-1.154743064*10^38*n^2+7.119519043*10^37*n^2*k1^2+6.495962587*10^37*k1*n^2-1.293058266*10^38*k2*n^2*k1-1.186994552*10^37*k2^2-1.708322740*10^38*k2*n+1.293058266*10^38*k2*n*k1+8.541613702*10^37*k2-3.529088273*10^37*k1-2.966874313*10^37*k1*n)/(1.620847396*10^9*n-1.620847396*10^9)

I want to simplify it. Obviously, it can be simplifed by simplifying the coeffecient of each terms. 

When I use 'simplify' command in Maple 18, I couldn't got what I want. 

Any suggetstions?

Thanks in advance.

I got a problem with solving a second order ODE. 

The ODE is :

-V(xi)+(1/2)*xi*(diff(V(xi), xi))+(1/4)*(diff(V(xi), xi, xi))=-(1/2)*k2*(diff(H(xi), xi))-k1*n*X/E+1+k2

where k1,k2,n,X,E  all are constant.

the condition is :

V(xi) tends to 2*xi^2 as xi tends to infinity.

I used 'dsolve' to solve the equation firstly, and got a solution with two constant C1 and C2, I want to use the condition to elimilate C2, so I used limit(sol,xi=infinity)=2*xi^2. But when I used the command 'limit', I can't get the answer.

Could any one help me? 

Many thanks!!!