using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var today = DateTime.Today;

        var data = Enumerable.Range(-12,42).Select(x=> new Account{CreatedOn = today.AddMonths(x), ClosedDate = today.AddMonths(x+3) } );

        var fromDate = today.AddMonths(-3);

        var toDate = today.AddMonths(3);

        Console.WriteLine("Data :"+data.Count()); data.Dump();

        var result = 

            data.Where( x => 

                     (x.CreatedOn >= fromDate && x.CreatedOn <= toDate)

                ||   (x.ClosedDate >= fromDate && x.ClosedDate <= toDate)

            );

        Console.WriteLine("\n\nResult"+result.Count()); result.Dump();

    }

    public class Account{

        public DateTime CreatedOn {get;set;}

        public DateTime ClosedDate {get;set;}       

    }

}