1-bit full adder is intended for add two binary operand (with size 1-bit). It has 3 inputs, that is first operand, second operand, and carry-in. Also it has 2 outputs, that is sum and carry-out.
1-bit full adder is expandable because if there's 1-bit full adder more where carry-in is connected to the carry-out of the another 1-bit full adder, it will create 2-bit adder that is intended for add two binary operand (with size 2-bit). So we can conclude n-bit adder is consist from many 1-bit full adders.
But why it's not applied to the 1-bit multiplier? What I mean with 1-bit multiplier is just simply an AND gate with two inputs and 1 output.
How do I make exapandable with just daisy chaining a 1-bit multiplier?