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JoyfulSilence · 46-50, M
Zero is an additive identity:
a + 0 = a
One is a multiplicative identity:
a * 1 = a
The zero matrix O (matrix of all zeros) is an additive identity:
A + O = A
The identity matrix I (capital letter I = square matrix that is one on the diagonal and zero elsewhere) is a multiplicative identity for square matrices A.
A * I = A = I * A
The identity function f is one where f(x) = x.
a + 0 = a
One is a multiplicative identity:
a * 1 = a
The zero matrix O (matrix of all zeros) is an additive identity:
A + O = A
The identity matrix I (capital letter I = square matrix that is one on the diagonal and zero elsewhere) is a multiplicative identity for square matrices A.
A * I = A = I * A
The identity function f is one where f(x) = x.