IGCSE CS Session 2 | Addition of Binary Numbers скачать в хорошем качестве

IGCSE CS Session 2 | Addition of Binary Numbers

🔹 Step 1: Review what binary is Before we start adding, let me remind you of something. In binary, we only have two digits: 0 1 This is different from decimal, where we use digits from 0 to 9. 🔹 Step 2: Binary addition rules (very important) Let’s start with the basic rules of binary addition. Please look at the table on the screen. Say slowly and point (or highlight): 0 + 0 = 0 0 + 1 = 1 1 + 0 = 1 1 + 1 = 10 This last one is very important. 1 + 1 does NOT equal 2 in binary. It equals 10. That means: We write 0 as the sum And we carry 1 to the next column 🔹 Step 3: Explain “carry” using decimal comparison This is similar to decimal addition. For example, when we add 7 + 9 in decimal: 7 + 9 = 16 We write 6 And we carry 1 In binary, we carry when the result is greater than 1. 🔹 Step 4: Adding column by column Now, when we add binary numbers, we always: Start from the right-hand side Add the digits in each column Include any carry Move left, one column at a time This is exactly the same idea as decimal addition. 🔹 Step 5: Adding three binary digits Sometimes, we add three digits: the first bit the second bit and the carry For example: 1 + 1 + 1 The result is 11 Sum = 1 Carry = 1 🔹 Step 6: Mention overflow (light introduction) When we use 8-bit binary numbers, there is a limit. The largest number we can store is 255. If the addition creates a 9th bit, this is called overflow. Overflow means: 👉 The result is too large to fit in 8 bits.