Multiplying Matrices Scalar Multiplication each element in a

Multiplying Matrices

Scalar Multiplication - each element in a matrix is multiplied by a constant.

**Multiply rows times columns. **You can only multiply if the number of columns in the 1 st matrix is equal to the number of rows in the 2 nd matrix. They must match. Dimensions: 2 x 3 3 x 2 The dimensions of your answer.

Examples: 2(3) + -1(5) 3(3) + 4(5) 2(-9) + -1(7) 2(2) + -1(-6) 3(-9) + 4(7) 3(2) + 4(-6)

Dimensions: 2 x 3 2 x 2 *They don’t match so can’t be multiplied together. *

*Answer should be a 2 x 2 2 x 2 0(4) + (-1)(-2) 1(4) + 0(-2) 2 x 2 0(-3) + (-1)(5) 1(-3) +0(5)

Sigmoid function

Sigmoid function 미분

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