Class 8 Mathematics Revision Notes
Rational Numbers Notes
Rational Numbers — Notes A rational number is any number of the form where are integers and . Properties Closure: rational numbers are closed under addition, subtraction and multi…
Linear Equations in One Variable Notes
Linear Equations in One Variable — Notes A linear equation has the variable to the power 1 and an equality sign. Solving equations Keep the equation balanced: do the same operatio…
Understanding Quadrilaterals Notes
Understanding Quadrilaterals — Notes Polygons A polygon is a closed figure made of line segments. It is convex if no interior angle is more than , otherwise concave . A regular po…
Squares and Square Roots Notes
Squares and Square Roots — Notes Square numbers A perfect square is a number obtained by squaring a whole number ( ). Squares end in or (never in ). A Pythagorean triplet satisfie…
Cubes and Cube Roots Notes
Cubes and Cube Roots — Notes Cubes A perfect cube is obtained by cubing a whole number ( ). A number is a perfect cube if, in its prime factorisation, every prime appears in group…
Comparing Quantities Notes
Comparing Quantities — Notes Percentages and money Discount Marked Price Sale Price; it is usually a percentage of the marked price. Profit/Loss percent is calculated on the cost…
Algebraic Expressions and Identities Notes
Algebraic Expressions and Identities — Notes Multiplication of expressions Monomial monomial: multiply coefficients and add powers of like variables. Use the distributive law for…
Mensuration Notes
Mensuration — Notes Areas Trapezium: , where are the parallel sides. Rhombus: (product of diagonals). General quadrilateral: split into triangles using a diagonal. Surface area an…
Exponents and Powers Notes
Exponents and Powers — Notes Negative exponents (for ). So . Laws of exponents For the same base : Standard form Very large and very small numbers are written as a number between…
Direct and Inverse Proportions Notes
Direct and Inverse Proportions — Notes Direct proportion Two quantities are in direct proportion if they increase or decrease together so that their ratio stays constant: Example:…
Factorisation Notes
Factorisation — Notes Factorisation means writing an expression as a product of its factors. Methods Common factors: take out the greatest common factor, e.g. . Regrouping terms:…
Introduction to Graphs Notes
Introduction to Graphs — Notes Graphs show information visually. Types of graphs Bar graph: compares quantities using bars. Pie chart: shows parts of a whole. Histogram: shows gro…