We all knew the formula for (a + b)² which is a² + 2ab + b² ,but do you knew the actual meaning behind it. Let’s find out.

(a + b)² is a Square with both sides (a+b) as shown in the figure 1.1.

Put a² and b² as shown in the figure 1.2.

Finally, Put 2ab as shown in the figure 1.3.

As we can see that the total area (a + b)² is covered by the a², b² and 2ab. This is only possible when a² + 2ab + b² is equal to (a + b)².

Hence, (a + b)² = a² + 2ab + b².