Public Function Integral(X)
A = 0
B = 1
H = 0.1
EPS = 0.5
N = (B - A) / H
For K = 1 To 10
INT1 = 0
For T = 0 To N Step H
INT1 = INT1 + Exp(-T) * T ^ (X - 1)
Next T
INT1 = INT1 * H
H = H / 2
N = (B - A) / H
INT2 = 0
For T = 0 To N Step H
INT2 = INT2 + Exp(-T) * T ^ (X - 1)
Next T
INT2 = IN2 * H
If Abs(INT1 - INT2) <= EPS Then
Exit For
End If
Next K
Integral = INT2
End Function