Class 9 Mathematics - Algebraic Identities Flashcards

A set of vocabulary flashcards defining key concepts and standard algebraic identity formulas for Class 9 Mathematics.

Algebraic Identity

An equality that is true for all allowed values of the variables.

Factorisation

Writing an expression as a product of simpler factors.

Square of Sum Identity

$$(a+b)^2 = a^2 + 2ab + b^2$$

Square of Difference Identity

$$(a-b)^2 = a^2 - 2ab + b^2$$

Difference of Squares Identity

$$a^2 - b^2 = (a-b)(a+b)$$

Product of Two Binomials Identity

$$(x+a)(x+b) = x^2 + (a+b)x + ab$$

Square of Three Terms Identity

$$(a+b+c)^2 = a^2 + b^2 + c^2 + 2ab + 2bc + 2ca$$

Cube of Sum Identity

$$(a+b)^3 = a^3 + 3a^2b + 3ab^2 + b^3$$

Cube of Difference Identity

$$(a-b)^3 = a^3 - 3a^2b + 3ab^2 - b^3$$

Sum of Cubes Identity

$$a^3 + b^3 = (a+b)(a^2 - ab + b^2)$$

Difference of Cubes Identity

$$a^3 - b^3 = (a-b)(a^2 + ab + b^2)$$