Filter Formulas

Identity I

Formula Easy

(x + y)2 = x2 + 2xy + y2

Variables: x, y
CBSE Class IX Mathematics Polynomials

Identity II

Formula Easy

(x – y)2 = x2 – 2xy + y2

Variables: x, y
CBSE Class IX Mathematics Polynomials

Identity III

Formula Easy

x2 – y2 = (x + y)(x – y)

Variables: x, y
CBSE Class IX Mathematics Polynomials

Identity IV

Formula Easy

(x + a)(x + b) = x2 + (a + b)x + ab

Variables: x, a, b
CBSE Class IX Mathematics Polynomials

Identity V

Formula Medium

(x + y + z)2 = x2 + y2 + z2 + 2xy + 2yz + 2zx

Variables: x, y, z
CBSE Class IX Mathematics Polynomials

Identity VI

Formula Medium

(x + y)3 = x3 + y3 + 3xy(x + y)

(x + y)3 = x3 + 3x2y + 3xy2 + y3

Variables: x, y
CBSE Class IX Mathematics Polynomials

Identity VII

Formula Medium

(x – y)3 = x3 – y3 – 3xy(x – y)

(x – y)3 = x3 – 3x2y + 3xy2 – y3

Variables: x, y
CBSE Class IX Mathematics Polynomials

Identity VIII

Formula Hard

x3 + y3 + z3 – 3xyz = (x + y + z)(x2 + y2 + z2 – xy – yz – zx)]

Variables: x, y, z
CBSE Class IX Mathematics Polynomials

Euclid’s postulates

Formula Easy
  • Postulate 1 : A straight line may be drawn from any one point to any other point.
  • Postulate 2 : A terminated line can be produced indefinitely.
  • Postulate 3 : A circle can be drawn with any centre and any radius.
  • Postulate 4 : All right angles are equal to one another.
CBSE Class IX Euclid’s Geometry Mathematics

Angles Opposite Equal Sides

Theorem Easy

Statement

Angles opposite to equal sides in a triangle are equal.

CBSE Class IX Mathematics Triangles

Congruent Circles

Theorem Easy

Statement

Two circles with equal radii are congruent.

CBSE Class IX Mathematics Triangles

Congruent Squares

Theorem Easy

Statement

Two squares with equal side lengths are congruent.

CBSE Class IX Mathematics Triangles