## The Square of a Binomial: (a + b)² = a² + 2ab + b²

The equation **(a + b)² = a² + 2ab + b²** is a fundamental algebraic identity known as the **square of a binomial**. This identity states that the square of the sum of two terms is equal to the square of the first term, plus twice the product of the two terms, plus the square of the second term.

### Understanding the Identity

**a**and**b**represent any two numbers, variables, or expressions.**(a + b)²**means the sum of**a**and**b**multiplied by itself: (a + b) * (a + b)**a²**represents**a**multiplied by itself.**2ab**represents twice the product of**a**and**b**.**b²**represents**b**multiplied by itself.

### Proof of the Identity

The identity can be proven using the distributive property of multiplication:

(a + b)² = (a + b) * (a + b)
= a(a + b) + b(a + b) // Expanding using distributive property
= a² + ab + ba + b² // Again, using distributive property
= **a² + 2ab + b²** // Combining like terms

### Applications of the Identity

The square of a binomial identity is widely used in various areas of mathematics and its applications:

**Algebraic Simplification:**It simplifies expressions involving squares of binomials.**Quadratic Equations:**It helps in solving quadratic equations by factoring them into the form (a + b)².**Geometry:**It applies in deriving area formulas for squares and rectangles.**Calculus:**It's used in calculating derivatives and integrals of expressions involving binomials.

### Example

Let's say we want to find the square of (x + 2):

(x + 2)² = x² + 2(x)(2) + 2² = **x² + 4x + 4**

### Conclusion

The square of a binomial identity is a powerful tool in algebra, providing a shortcut to expand expressions and simplify equations. It is an essential concept to understand for solving various mathematical problems and further exploring the fascinating world of algebra.