Excel MMULT function

Function              MMULT

Description        Excel MMULT function returns the matrix product of two arrays.

Syntax  MMULT(array1, array2)

array1  The first array or matrix to multiply.

array2  The second array or matrix to multiply.

Example:

See here =MMULT($C$2:$D$3,$F$2:$G$3) means =MMULT({2,3;4,5},{6,9;7,8})=2*6+3*7

Rules of matrix multiplication.