Two's Complement Method

Notes about the $2$'s complement method:

• Adding numbers is even more simple: if you get an end-around carry, just discard it (you don't add it back to the result.) This improvement makes the computer run addition even faster!
• Zero ($0$) has only one representation: $0000...000$!
• $2$'s complement is what computers use nowadays to represent numbers!

Fun Activity №1: Represent the following in $8$-bit, $2$'s complement format: (1) $9_{10}$ (2) $-9_{10}$ (3) $-17_{10}$.

Fun Activity №2: Represent the following $2$'s complement numbers as decimal numbers: (1) $01001011_{2}$ (2) $11010010_{2}$ (3) $10000000_{2}$.

Let's now see how to add numbers in $2$'s complement format.