Free Calculus Textbooks (PDF): Legal, Open-Licensed Books
The best free calculus textbooks you can legally download as PDFs: OpenStax, Active Calculus, APEX Calculus, Strang’s Calculus and Calculus Made Easy.
Month: October 2026
Read article → Free Calculus Textbooks (PDF): Legal, Open-Licensed Books
Fractions: How to Add, Subtract, Multiply and Divide
How to add, subtract, multiply and divide fractions, simplify them, convert mixed numbers and compare fractions, with step-by-step examples.
Exponential Functions: Definition, Graphs, Growth and Decay
Exponential functions explained: graphs and asymptotes, the number e, growth and decay models, compound interest, and solving exponential equations.
Exponent Rules: Laws of Exponents with Examples
All the exponent rules: product, quotient, power, zero, negative and fractional exponents, with worked examples, scientific notation and common mistakes.
Domain and Range of a Function: How to Find Them
How to find the domain and range of a function from its equation or graph, with interval notation, asymptotes, inverse functions and worked examples.
Distance Formula and Midpoint Formula with Examples
The distance and midpoint formulas: where they come from, examples with negative coordinates, finding a missing endpoint, 3D distance and practice.
Differential Equations: An Introduction with Examples
What a differential equation is, how to solve separable and first-order linear equations and initial value problems, real models, and Euler’s method.
Derivative Rules: Every Differentiation Formula, Explained
All the derivative rules in one place: definition, power, product (uv), quotient and chain rules, plus trig, exponential, log and inverse trig derivatives.
Derivative of sin x: Proof, Examples and Trig Derivatives
The derivative of sin x is cos x. See the limit proof, chain rule examples like sin(3x) and sin²x, and the table of all six trig derivatives.
Degrees to Radians and Radians to Degrees: Formula, Chart
Convert degrees to radians (multiply by π/180) and radians to degrees (multiply by 180/π), with a full chart, unit circle radians and examples.