Class 11 Maths Notes

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Class 11 Maths Notes

One place for all your Class 11 Maths revision, arranged in the official NCERT order. The course opens with sets, relations and functions, then trigonometric functions, followed by the algebra of complex numbers, linear inequalities, permutations and combinations, the binomial theorem and sequences and series. It ends with coordinate geometry (straight lines and conic sections), an introduction to three dimensional geometry, limits and derivatives, statistics and probability. Each chapter has key formulas, exam pointers and solved examples — written for CBSE boards, JEE Main and the Class 11 foundation NEET students build on.

Class:11Subject:MathematicsCovers:CBSE · JEE

7 Key Formulas

DWritten byDeep Narayan

UpdatedSeptember 2026

Key Concept Summary

What is covered in Class 11 Maths?

Class 11 Maths has 14 chapters: sets; relations and functions; trigonometric functions; complex numbers and quadratic equations; linear inequalities; permutations and combinations; binomial theorem; sequences and series; straight lines; conic sections; introduction to three dimensional geometry; limits and derivatives; statistics; and probability.

About the Class 11 Maths Notes

These chapter-wise notes condense the complete Class 11 mathematics syllabus into quick-revision sheets. Each chapter page gives you the essential concepts, the key formulas together, exam pointers for the exam hall, and a quick FAQ answering the most-asked questions.

How to use these notes

Use each chapter page for last-minute revision: read the quick answer, scan the key formulas, then test yourself with the exam pointers. Algebra and calculus carry the biggest share of JEE marks, so master complex numbers, sequences, and limits and derivatives early.

Follows the NCERT chapter order

This note lists every chapter in the official NCERT order, from Sets (Chapter 1) through Probability (Chapter 14), so the sequence matches the book you study from. Every chapter now has its own dedicated revision page.

Sets, Relations, Functions and Trigonometry (Chapters 1–3)

Sets — representation, types of sets, subsets and power sets, union, intersection and complement, De Morgan's laws and cardinality problems.
Relations and Functions — Cartesian products, relations, one-one and onto functions, standard real functions and graphs.
Trigonometric Functions — degree and radian measure, compound-angle formulas, sum-to-product identities, general solutions and the sine and cosine rules.

Two-set inclusion–exclusion

n (A \cup B) = n (A) + n (B) - n (A \cap B)

Foundation of Class 12 maths

Sets, functions and trigonometry are the ideas Class 12 calculus and inverse trigonometry build on. Solidifying them now makes continuity, differentiation and integration noticeably easier later.

Complex Numbers and Algebra (Chapters 4–8)

Complex Numbers — conjugate, modulus, polar form and roots of quadratic equations with real coefficients.
Linear Inequalities — algebra of inequalities, absolute-value inequalities and graphical regions.
Permutations and Combinations — the fundamental principle of counting, nPr, nCr and arrangements with identical objects.
Binomial Theorem — the general term, middle term and properties of binomial coefficients.
Sequences and Series — arithmetic and geometric progressions, AM and GM, and sums of special series.

Permutations and combinations

^{n} P_{r} = \frac{n !}{( n - r )!},^{n} C_{r} = \frac{n !}{r ! ( n - r )!}

Counting is a JEE favourite

Permutations, combinations and the binomial theorem generate a large number of JEE questions and are quick to score once the factorial formulas are automatic. Practise standard selection problems until the patterns are familiar.

Coordinate Geometry (Chapters 9–11)

Straight Lines — slope, the various equation forms, angle between two lines and distance formulas.
Conic Sections — circle, parabola, ellipse and hyperbola with focus, directrix, eccentricity and latus rectum.
Introduction to Three Dimensional Geometry — distance between points, section formula, direction cosines and direction ratios.

Ellipse in standard form

\frac{x ^{2}}{a ^{2}} + \frac{y ^{2}}{b ^{2}} = 1, e = 1 - \frac{b ^{2}}{a ^{2}}

Carries over to Class 12

Straight lines and conic sections feed directly into Class 12 vector algebra and three dimensional geometry, while the 3D chapter here introduces the direction cosines Class 12 expands on.

Calculus, Statistics and Probability (Chapters 12–14)

Limits and Derivatives — left and right limits, standard limits, and derivatives from first principles with the algebra of derivatives.
Statistics — mean deviation, variance and standard deviation for grouped and ungrouped data, and the coefficient of variation.
Probability — sample space, events, the axioms of probability and the addition theorem.

First principles and the fundamental limit

f^{'} (x) = h \to 0 lim \frac{f ( x + h ) - f ( x )}{h}, x \to 0 lim \frac{sin x}{x} = 1

Calculus gate to Class 12

Limits and derivatives is where Class 12 differentiation begins. The first-principles definition and the standard limits reappear throughout Class 12 calculus, boards and JEE.

Quick Revision

Key formulas at a glance

Memorise these equations — direct application numericals and derivations in CBSE & JEE frequently hinge on these.

Two-set union

n (A \cup B) = n (A) + n (B) - n (A \cap B)

Permutation

^{n} P_{r} = \frac{n !}{( n - r )!}

Combination

^{n} C_{r} = \frac{n !}{r ! ( n - r )!}

Sum of an AP

S_{n} = \frac{n}{2} [2 a + (n - 1) d]

Sum of an infinite GP

S_{\infty} = \frac{a}{1 - r}, ∣ r ∣ < 1

Binomial general term

T_{r + 1} =^{n} C_{r} a^{n - r} b^{r}

Fundamental limit

x \to 0 lim \frac{sin x}{x} = 1

Exam Strategy

How this chapter is asked

High-yield question patterns observed across CBSE boards, JEE Main & Advanced, and NEET.

A set with n elements has 2ⁿ subsets, including the empty set and itself.
nPr = r! × nCr connects permutations and combinations.
The sum of n terms of an AP is n/2 (2a + (n−1)d); an infinite GP sums to a/(1−r) only for |r| < 1.
The general term of (a + b)ⁿ is nCr aⁿ⁻ʳ bʳ, with the middle term depending on whether n is even or odd.
For a parabola y² = 4ax the focus is (a, 0) and the latus rectum is 4a.
lim_{x→0} sinx/x = 1 and (1−cosx)/x² → 1/2 are the twin workhorses of limits.
σ² = Σ(x − x̄)²/ n and the coefficient of variation CV = (σ/x̄) × 100 compare two distributions.
The probability of an event satisfies 0 ≤ P(A) ≤ 1 and P(A′) = 1 − P(A).

FAQ

Frequently asked questions

How many chapters are there in Class 11 Maths?

Exactly 14: sets; relations and functions; trigonometric functions; complex numbers and quadratic equations; linear inequalities; permutations and combinations; binomial theorem; sequences and series; straight lines; conic sections; introduction to three dimensional geometry; limits and derivatives; statistics; and probability. This hub links each chapter's dedicated revision notes.

Which Class 11 maths topics are most important for JEE?

Algebra (complex numbers, permutations and combinations, binomial theorem, sequences and series) and calculus (limits and derivatives) carry the largest weight in JEE Main, followed by coordinate geometry. These topics also lay the ground for nearly all of Class 12 calculus.

Is Class 11 maths needed for NEET?

Maths is not tested in NEET, but Class 11 trigonometry and limits and derivatives underpin the physics chapters on kinematics, motion and oscillations, so a working command of these topics saves time in physics preparation.

How should I revise Class 11 maths?

Practise the core formulas — nCr and nPr, AP and GP sums, the binomial general term, standard limits — then solve past board and JEE-style problems. Use the key-formulas and exam pointers on each chapter page as your last-minute revision sheet.

Next Chapters

Continue learning

Sets Notes Class 11 Maths NCERT Solutions Relations and Functions Notes Trigonometric Functions Notes Complex Numbers Notes Linear Inequalities Notes Permutations and Combinations Notes Binomial Theorem Notes Sequences and Series Notes Straight Lines Notes Conic Sections Notes Three Dimensional Geometry Notes Limits and Derivatives Notes Statistics Notes Probability Notes Maths Tutor in Mohali

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Class 11 Maths NCERT Solutions (Chapter-Wise Solved)

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