Sub Buscaleatoria()

    Dim maxf As Single, maxx As Single, maxy As Single
    'Dim i As Integer, j As Integer, n As Integer
    Dim i As Long, j As Long, n As Long
    Dim x As Single, y As Single
    Dim fxy As Single
    Dim r As Range
    
    
    Set r = Range("a10")
    maxf = -1000000000#
    For i = 1 To 6
        n = 10 ^ i
        For j = 1 To n
            x = -2 + 4 * Rnd
            y = 1 + 2 * Rnd
            fxy = y - x - 2 * x ^ 2 - 2 * x * y - y ^ 2
            If fxy > maxf Then
                maxf = fxy
                maxx = x
                maxy = y
            End If
        Next j
        r(i, 1) = n
        r(i, 2) = maxx
        r(i, 3) = maxy
        r(i, 4) = maxf
    Next i


End Sub