Perform the following decimal subtraction problems using binary numbers in a 4-bit word. Use 2's complement notation to convert the subtraction problem into an equivalent addition problem. Then carry out the binary addition. Show your work and your carry bits as in the previous examples. Indicate when an overflow occurs.

From +2 subtract + 2
The subtraction problem is: +2 — (+2)
The equivalent addition problem is: +2 + (-2)

First find the 2's complement of +2. This will be the representation of— 2.
Start with +2: 0010
Flip the bits: 1101
Add one to get —2: 1110
Add 0010 (+ 2) and 1110 (-2) to get 0000 (0)
Carry bit: 1 1 1 0
First number: 1 1 1 0 (— 2)
Second number: 0 0 1 0 (+ 2)
Result: * 0 0 0 0 (+ 0) * The final carry is discarded