Sub Макрос1()

    Dim a As Double
    Dim b As Double
    Dim c As Double

    [C2].value = ""
    [C3].value = ""
    [C4].value = ""
    [C5].value = ""

    a = [B2].value
    b = [B3].value
    c = [B4].value

    If (a < 0 Or b < 0 Or c < 0) Then
        If (a < 0) Then
            [C2].value = "Отрицательное"
        End If
        If (b < 0) Then
            [C3].value = "Отрицательное"
        End If
        If (c < 0) Then
            [C4].value = "Отрицательное"
        End If
    Else
        [C5].value = "Все значения положительные"

    End If

End Sub