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DL-C02-C-001
Substitute the values into wx + b.
DL-C02-C-002
theta is the usual compact symbol for parameters.
DL-C02-C-003
First compute (12, 5) x (5, 4). Then add the bias.
DL-C02-C-004
The hat usually marks the model's estimate or prediction.
DL-C02-C-005
Use prediction minus target.
DL-C02-C-006
The architecture defines the family. The parameters choose within it.