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Fri, 22 May 2026 07:32:28 GMT https://openfreebooks.org/math/written-calculation/ https://openfreebooks.org/math/written-calculation/ Fri, 22 May 2026 07:32:28 GMT Add, subtract, multiply, and divide whole numbers using vertical written form: align columns, regroup, and read the result. https://openfreebooks.org/math/pythagoras-theorem/ https://openfreebooks.org/math/pythagoras-theorem/ Fri, 22 May 2026 06:55:33 GMT Use Pythagoras' theorem and its converse in 2D problems and coordinate settings. https://openfreebooks.org/math/algebraic-fractions-formulas/ https://openfreebooks.org/math/algebraic-fractions-formulas/ Fri, 22 May 2026 06:25:20 GMT Simplify and combine algebraic fractions; rearrange formulas in science contexts. https://openfreebooks.org/math/counting-and-numbers/ https://openfreebooks.org/math/counting-and-numbers/ Fri, 22 May 2026 06:25:20 GMT Count objects, spot patterns, add, multiply, and divide; then meet place value and big numbers from hundreds to billions. https://openfreebooks.org/math/zero-and-one/ https://openfreebooks.org/math/zero-and-one/ Fri, 22 May 2026 05:57:59 GMT 0 is nothing; 1 is one. Learn to tell them apart — the same skill as telling false from true — before counting larger amounts. https://openfreebooks.org/math/coordinate-geometry-foundations/ https://openfreebooks.org/math/coordinate-geometry-foundations/ Fri, 22 May 2026 05:18:34 GMT Plot points, find distances and midpoints, and work with slopes of lines in the Cartesian plane. https://openfreebooks.org/math/basic-math-notation/ https://openfreebooks.org/math/basic-math-notation/ Thu, 21 May 2026 23:42:19 GMT Learn the names and meanings of plus, minus, times, divide, equals, brackets, and other signs used in number sentences. https://openfreebooks.org/math/integer-foundations/ https://openfreebooks.org/math/integer-foundations/ Thu, 21 May 2026 23:42:19 GMT Model directed magnitude on number lines; use the zero principle and tiles to add and subtract integers, and see subtraction as adding an opposite. https://openfreebooks.org/math/percentage-applications/ https://openfreebooks.org/math/percentage-applications/ Thu, 21 May 2026 23:42:19 GMT Relate fractions and decimals to base-100 ratios; calculate percent increase and decrease in financial and real-world contexts. https://openfreebooks.org/contributing/ https://openfreebooks.org/contributing/ Thu, 21 May 2026 18:40:42 GMT Contribute https://openfreebooks.org/math/rational-number-operations/ https://openfreebooks.org/math/rational-number-operations/ Thu, 21 May 2026 17:54:08 GMT Convert between fractions, terminating decimals, and repeating decimals; add, subtract, multiply, and divide rational numbers and mixed numbers. https://openfreebooks.org/math/ratios-and-rates-foundation/ https://openfreebooks.org/math/ratios-and-rates-foundation/ Thu, 21 May 2026 17:54:08 GMT Formulate part-to-part and part-to-whole ratios, find equivalent ratios, compute unit rates, and graph proportional relationships. https://openfreebooks.org/math/advanced-trigonometry/ https://openfreebooks.org/math/advanced-trigonometry/ Thu, 21 May 2026 16:54:30 GMT Use sine and cosine rules, radians, and trigonometric graphs in 2D and 3D applications. https://openfreebooks.org/math/basic-probability/ https://openfreebooks.org/math/basic-probability/ Thu, 21 May 2026 16:54:30 GMT Calculate theoretical and experimental probabilities for simple events and complements. https://openfreebooks.org/math/circle-properties/ https://openfreebooks.org/math/circle-properties/ Thu, 21 May 2026 16:54:30 GMT Apply chord, tangent, and angle theorems in circles to prove results and solve geometry problems. https://openfreebooks.org/math/congruence-similarity/ https://openfreebooks.org/math/congruence-similarity/ Thu, 21 May 2026 16:54:30 GMT Apply congruence and similarity criteria to justify properties of triangles and scale figures. https://openfreebooks.org/math/coordinate-circles/ https://openfreebooks.org/math/coordinate-circles/ Thu, 21 May 2026 16:54:30 GMT Find equations of circles, tangents, and intersections using coordinate methods and distance. https://openfreebooks.org/math/deductive-geometry/ https://openfreebooks.org/math/deductive-geometry/ Thu, 21 May 2026 16:54:30 GMT Prove angle and side relationships for intersecting lines, triangles, and polygons. https://openfreebooks.org/math/introduction-trigonometry/ https://openfreebooks.org/math/introduction-trigonometry/ Thu, 21 May 2026 16:54:30 GMT Define sine, cosine, and tangent ratios and solve right-angled triangle problems. https://openfreebooks.org/math/loci/ https://openfreebooks.org/math/loci/ Thu, 21 May 2026 16:54:30 GMT Describe and construct loci in the plane, linking geometric constraints to algebraic equations. https://openfreebooks.org/math/measures-dispersion/ https://openfreebooks.org/math/measures-dispersion/ Thu, 21 May 2026 16:54:30 GMT Interpret range, interquartile range, variance, and standard deviation for comparing data sets. https://openfreebooks.org/math/mensuration-3d/ https://openfreebooks.org/math/mensuration-3d/ Thu, 21 May 2026 16:54:30 GMT Find volumes and surface areas of prisms, cylinders, pyramids, cones, and spheres. https://openfreebooks.org/math/normal-distribution-z-scores/ https://openfreebooks.org/math/normal-distribution-z-scores/ Thu, 21 May 2026 16:54:30 GMT Model continuous data with the normal curve, standardise with z-scores, and read probabilities from tables. https://openfreebooks.org/math/permutations-combinations-probability/ https://openfreebooks.org/math/permutations-combinations-probability/ Thu, 21 May 2026 16:54:30 GMT Count outcomes with permutations and combinations, then compute probabilities in finite sample spaces. https://openfreebooks.org/math/statistical-charts-averages/ https://openfreebooks.org/math/statistical-charts-averages/ Thu, 21 May 2026 16:54:30 GMT Organise data with tables and charts and calculate mean, median, and mode. https://openfreebooks.org/math/statistical-literacy/ https://openfreebooks.org/math/statistical-literacy/ Thu, 21 May 2026 16:54:30 GMT Evaluate claims in media and research: sampling bias, correlation versus causation, and misleading charts. https://openfreebooks.org/math/complex-numbers/ https://openfreebooks.org/math/complex-numbers/ Thu, 21 May 2026 07:33:01 GMT Represent complex numbers in Cartesian form and perform operations including conjugates and division. https://openfreebooks.org/math/exponential-logarithmic/ https://openfreebooks.org/math/exponential-logarithmic/ Thu, 21 May 2026 07:33:01 GMT Use exponential and logarithmic models, apply log laws, and solve growth and decay equations. https://openfreebooks.org/math/factor-remainder-theorems/ https://openfreebooks.org/math/factor-remainder-theorems/ Thu, 21 May 2026 07:33:01 GMT Use the factor and remainder theorems to factorise higher-degree polynomials and solve related equations. https://openfreebooks.org/math/functions-graphs/ https://openfreebooks.org/math/functions-graphs/ Thu, 21 May 2026 07:33:01 GMT Model input-output rules, work with domain and range, and sketch key function graphs and transformations. https://openfreebooks.org/math/linear-equations-two-unknowns/ https://openfreebooks.org/math/linear-equations-two-unknowns/ Thu, 21 May 2026 07:33:01 GMT Solve pairs of linear equations by substitution, elimination, and graphs; classify unique, parallel, and coincident cases. https://openfreebooks.org/math/linear-programming/ https://openfreebooks.org/math/linear-programming/ Thu, 21 May 2026 07:33:01 GMT Graph linear inequalities, identify feasible regions, and optimise objective functions in two variables. https://openfreebooks.org/math/sequences-series/ https://openfreebooks.org/math/sequences-series/ Thu, 21 May 2026 07:33:01 GMT Work with arithmetic and geometric sequences, sigma notation, and finite summation formulas. https://openfreebooks.org/math/variations/ https://openfreebooks.org/math/variations/ Thu, 21 May 2026 07:33:01 GMT Model direct, inverse, joint, and partial variation and solve combined variation problems. https://openfreebooks.org/math/laws-of-indices/ https://openfreebooks.org/math/laws-of-indices/ Thu, 21 May 2026 06:54:57 GMT Apply index laws to simplify expressions with integer and rational exponents. https://openfreebooks.org/math/linear-inequalities-one-unknown/ https://openfreebooks.org/math/linear-inequalities-one-unknown/ Thu, 21 May 2026 06:54:57 GMT Solve, represent, and apply linear inequalities in one unknown using number lines and interval notation. https://openfreebooks.org/faq/ https://openfreebooks.org/faq/ Thu, 21 May 2026 02:10:55 GMT FAQ https://openfreebooks.org/physics/ https://openfreebooks.org/physics/ Thu, 21 May 2026 02:10:55 GMT Browse physics chapters in the curriculum catalog. https://openfreebooks.org/physics/force-newtons-laws/ https://openfreebooks.org/physics/force-newtons-laws/ Thu, 21 May 2026 02:10:55 GMT Use free-body diagrams, F = ma, and motion graphs to predict how objects move. https://openfreebooks.org/math/polynomials-expansion-factorisation/ https://openfreebooks.org/math/polynomials-expansion-factorisation/ Wed, 20 May 2026 20:17:25 GMT Expand products, collect like terms, and factorise expressions using common factors and identities. https://openfreebooks.org/math/properties-of-operations/ https://openfreebooks.org/math/properties-of-operations/ Wed, 20 May 2026 20:17:25 GMT See why order, grouping, and distribution can change how you write a sum or product without changing the result — with interactive area and dot models. https://openfreebooks.org/math/quadratic-equations/ https://openfreebooks.org/math/quadratic-equations/ Wed, 20 May 2026 20:17:25 GMT The discriminant, nature of roots, and the graph of y = ax² + bx + c. https://openfreebooks.org/search/ https://openfreebooks.org/search/ Tue, 19 May 2026 19:29:49 GMT Search https://openfreebooks.org/math/ https://openfreebooks.org/math/ Tue, 19 May 2026 10:55:50 GMT Browse mathematics chapters in the curriculum catalog. https://openfreebooks.org/catalog/ https://openfreebooks.org/catalog/ Tue, 19 May 2026 10:40:53 GMT Catalog https://openfreebooks.org/about/ https://openfreebooks.org/about/ Tue, 19 May 2026 06:35:42 GMT Manifesto https://openfreebooks.org/credits/ https://openfreebooks.org/credits/ Tue, 19 May 2026 05:33:20 GMT Credits https://openfreebooks.org/ https://openfreebooks.org/ Tue, 19 May 2026 04:06:12 GMT Free, open-source textbooks for every learner — elementary through university. 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