Formula

(2 + 3)²

25

25

(2 + 3)² equals 25.

How this was calculated
(a + b)² = a² + 2ab + b²
a² = 4, 2ab = 12, b² = 9
= 4 + 12 + 9 = 25

First binomial formula: the square of a sum is a² plus twice the product 2ab plus b².

a = 2b = 3aba² = 4ab = 6ab = 6b² = 9
(a + b)²
25
(a − b)²
1
(a + b)(a − b)
-5

Rewrite a term with variables

Enter brackets to expand, enter a sum to factorise. Powers with ^ or ², the multiplication sign can be omitted.

(3x + 2y)^2 = 9x² + 12xy + 4y²

Expanded with the 1st binomial formula.

(a + b)² = a² + 2ab + b²
a = 3x, b = 2y
= (3x)² + 2 · (3x) · (2y) + (2y)²
= 9x² + 12xy + 4y²

Binomial Formulas by Rechnerzentrale(opens in a new tab)