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记录

#include<iostream>
#include<iomanip>
#include<cmath>
using namespace std;
double a,b,c,d,L,R;
double f(double x)
{
    return (c * x) / a + (d / a - b * c / a / a) * log(abs(a * x + b));
}
int main()
{
    cin >> a >> b >> c >> d >> L >> R;
    cout << setprecision(6) << f(R) - f(L);
    return 0;
}