Notation For The Elements of a Matrix –
An element of a matrix, appearing in the i-th row and e-th column is called the (i, e)th element of the matrix and it is denoted by aᵢₑ.
Thus, a matrix A of order (m X n) is written as –
A = [aᵢₑ]ᵤ ₓ ᵥ
a₁₁ = element in 1st row and 1st column
a₁₂ = element in 1st row and 2nd column
a₁₃ = element in 1st row and 3rd column
a₂₁ = element in 2nd row and 1st column
a₂₂ = element in 2nd row and 2nd column
a₂₃ = element in 2nd row and 3rd column
a₃₁ = element in 3rd row and 1st column
a₃₂ = element in 3rd row and 2nd column
a₃₃ = element in 3rd row and 3rd column
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