Class 9 Mathematics Notes

The Cartesian plane, axes, quadrants, plotting points and the distance between points.

Linear expressions and polynomials, their graphs, zeroes and linear patterns in daily life.

Natural, whole, integer, rational and irrational numbers, real numbers, decimals and surds.

Square and cube identities, their geometric meaning and use in factorisation.

Periodic patterns and circular motion: angles, circles, chords and repeating behaviour.

Perimeter and area of polygons and circles, Heron’s formula and derivations of area formulas.

Randomness, experimental and theoretical probability, tables and tree diagrams.

Sequences, arithmetic and geometric progressions, recursive rules and visual patterns.

Mathematical statements, implications, converses, counter-examples and simple proofs in geometry.

Organising and representing data, measures of central tendency and interpreting graphs.

Step-by-step procedures, flowcharts, Euclid’s division algorithm and algorithmic thinking.

Properties of parallelograms, the mid-point theorem and conditions for special quadrilaterals.

Linear equations in two variables, their graphs and solving pairs by substitution, elimination and graphs.

Surface area and volume of cuboids, cylinders, cones, spheres and hemispheres.