Matrix Functions

Multiplying - MMULT

the matrices must both be square and of the same dimension

Public Sub Testing() 
Dim varray1 As Variant 
Dim varray2 As Variant 
Dim vreturn As Variant 

    varray1 = Sheets("Sheet1").Range("B2:C3").Value 
    varray2 = Sheets("Sheet1").Range("B5:C6").Value 
   
    vreturn = Multiply_Matrices(varray1, varray2) 
    
    'call msgbox(vreturn
End Sub 

Public Function Multiply_Matrices( _ 
    ByVal Arg1 As Variant, _ 
    ByVal Arg2 As Variant) As Variant 

Dim vreturn As Variant 
    vreturn = Application.WorksheetFunction.MMult(Arg1, Arg2) 

    Multiply_Matrices = vreturn 
End Function 

When you take data directly off a worksheet by assigning a range to a Variant data type the array will be 1 based.
SS of watch window

Inverting - MINVERSE

the matrices must both be square and of the same dimension

Transposing - TRANSPOSE