# ${(a-b)}^2$ Formula

## Formula

${(a-b)}^2 \,=\, a^2+b^2-2ab$

It is called $a-b$ whole square formula. It is read as the $a$ minus $b$ whole square is equal to $a$ squared plus $b$ squared minus $2ab$. The algebraic identity represents the expansion of the subtraction of two terms and also useful in mathematics to expand the subtraction basis binomials.

### Proof

The $a-b$ whole square algebraic identity can be proved in two different mathematical approaches.

01

#### Algebraic Method

The expansion of square of $a-b$ formula is derived in algebraic mathematics by the multiplication of algebraic expressions.

02

#### Geometrical Method

The square of subtraction of the terms can be expanded by proving it in geometrical approach on the basis of areas of square and rectangle.