XL 2010 Produit matriciel avec une matrice inverse

MatriceX2(i - 1, 0) = P(i, 1) * X(i - 1, 0) + _
                      P(i, 2) * X(i - 1, 0) + _
                      P(i, 3) * X(i - 1, 0)

   Function Pinv(Angle As Double) As Variant
        Dim Matinverse() As Variant
        
        'Calcul de la matrice inverse
        
        Matinverse = Application.MInverse(Range("B27:D29"))
        
        For i = 1 To 3
            For j = 1 To 3
                                        
                 Cells(46 + i, 1 + j) = Matinverse(i - 1, j - 1)
                
            Next j
        Next i
        
        
        Pinv = Matinverse
    
    
    End Function

    
    Function Mat_X(Angle As Double) As Variant
        Dim MatIntX(3, 1) As Double
        
        'Détermination de la matrice X
        
        MatIntX(0, 0) = Cells(5, 8)
        MatIntX(1, 0) = Cells(6, 8)
        MatIntX(2, 0) = Cells(7, 8)
        
        Mat_X = MatIntX
    
    End Function
    
    
    Function Mat_ProdPX(Angle As Double) As Variant
    'M1M2 = P
    'X2 = X'
    
    'Initialisation
        Dim MatriceX2(3, 1) As Double
        Dim P As Variant
        Dim X As Variant
        Dim i, j As Integer
      
        
     'Calcule de X'=Pinv*X
    
        P = Pinv(Angle)
        X = Mat_X(Angle)
      
        
        For i = 1 To 3
        
                MatriceX2(i - 1, 0) = P(i, 1) * X(i - 1, 0) + _
                      P(i, 2) * X(i - 1, 0) + _
                      P(i, 3) * X(i - 1, 0)
            
                    
                Cells(13 + i, 8) = MatriceX2(i - 1, 0)
                
        Next i

    

    End Function

MatriceX2(i - 1, 0) = P(i, 1) * X(i - 1, 0) + _
                      P(i, 2) * X(i - 1, 0) + _
                      P(i, 3) * X(i - 1, 0)