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Class 11 Maths Formula Sheet 2026-27 — All 14 Chapters in One Page

Every formula from all 14 chapters, memory tricks that actually stick, and the exact question patterns CBSE repeats every year.

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Option 1 (H1): Class 11 Maths Formula Sheet 2026-27 — All 14 Chapters in One Page
Meta: Free CBSE Class 11 Maths formula sheet covering all 14 chapters — Sets to Probability — with quick revision cheatsheet and memory tricks.

Option 2 (H1): CBSE Class 11 Maths All Formulas Cheatsheet (2026-27 Syllabus)
Meta: Every Class 11 Maths formula you need — Trigonometry, Complex Numbers, Sequences & Series, Conic Sections, Limits & Derivatives, Statistics, and Probability.

Option 3 (H1): Class 11 Maths Quick Revision Formulas — Back Bencher Class Edition
Meta: Struggling to remember Class 11 Maths formulas before the exam? Every formula, memory trick, and exam pattern from all 14 chapters in one simple page.

Formulas Bhool Jaate Ho? Chill, Hum Hain Na 🎸

Exam se ek raat pehle formula yaad karne ki tension har back bencher jaanta hai. Isliye ye page bana hai — Class 11 Maths ke 14 chapters ke formulas, ek hi jagah, bina kisi bhaari-bharkam jargon ke. Scroll karo, jo chapter revise karna hai wahan jump karo, aur exam hall mein confidently likho.

Quick Jump — All Chapters

Ch 1: Sets Ch 2: Relations and Functions Ch 3: Trigonometric Functions Ch 4: Complex Numbers and Quadratic Equations Ch 5: Linear Inequalities Ch 6: Permutations and Combinations Ch 7: Binomial Theorem Ch 8: Sequences and Series Ch 9: Straight Lines Ch 10: Conic Sections Ch 11: Introduction to Three Dimensional Geometry Ch 12: Limits and Derivatives Ch 13: Statistics Ch 14: Probability

Chapter-Wise Formulas, Tricks & Exam Patterns

Chapter 1

Sets — All Formulas

n(A∪B) = n(A) + n(B) - n(A∩B)

n(A∪B∪C) = n(A)+n(B)+n(C)-n(A∩B)-n(B∩C)-n(A∩C)+n(A∩B∩C)

Number of subsets of a set with n elements = 2ⁿ

Power set P(A) = set of all subsets of A

💡 Pro-Tip / Memory Trick:

For n(A∪B), think 'add both, minus the overlap you double-counted' — draw a quick Venn diagram if the formula slips your mind under pressure.

📝 Most Repeated Board Question Pattern:

Word problems using Venn diagrams (students who play cricket/football etc.) applying the union-intersection formula — 3-5 marks.

Chapter 2

Relations and Functions — All Formulas

If n(A)=m, n(B)=n, then n(A×B) = mn

Number of relations from A to B = 2^(mn)

A relation f is a function if every element of domain maps to exactly one element of range

💡 Pro-Tip / Memory Trick:

Cartesian product count is just multiplication (m×n) — don't confuse it with number of relations, which is 2 raised to that product.

📝 Most Repeated Board Question Pattern:

Find the domain and range of a given function, or determine whether a given relation is a function — 2-4 marks.

Chapter 3

Trigonometric Functions — All Formulas

sin²x + cos²x = 1

sin(x+y) = sinx cosy + cosx siny

cos(x+y) = cosx cosy - sinx siny

tan(x+y) = (tanx+tany)/(1-tanx tany)

Radian measure: θ (radians) = (π/180) × degree measure

💡 Pro-Tip / Memory Trick:

Whenever you see a sum/difference formula, remember: sin keeps the same signs pattern (+ for sum), cos flips signs (- for sum) — this pattern extends to double and triple angle formulas too.

📝 Most Repeated Board Question Pattern:

Prove trigonometric identities, or find values of trigonometric functions at compound angles using standard sum/difference formulas — 3-5 marks, very frequent.

Chapter 4

Complex Numbers and Quadratic Equations — All Formulas

i² = -1

z = a + ib, |z| = √(a²+b²)

Conjugate of z = a+ib is z̄ = a-ib

For ax²+bx+c=0 with D<0, roots are complex: x = [-b ± i√(4ac-b²)]/2a

💡 Pro-Tip / Memory Trick:

Whenever discriminant D is negative, don't panic and say 'no solution' — in this chapter, negative D means complex roots exist, just written using i.

📝 Most Repeated Board Question Pattern:

Express a complex number in standard form a+ib and find its modulus/conjugate, or solve a quadratic with negative discriminant — 2-3 marks.

Chapter 5

Linear Inequalities — All Formulas

If a < b, then a+c < b+c (adding same number preserves inequality)

If a < b and c < 0, then ac > bc (multiplying by negative flips the sign)

💡 Pro-Tip / Memory Trick:

The ONE rule that decides everything in this chapter: multiplying or dividing an inequality by a negative number flips the inequality sign — forgetting this single rule is the most common mistake in the entire chapter.

📝 Most Repeated Board Question Pattern:

Solve a linear inequality algebraically and represent the solution on a number line, or solve a system of two inequalities graphically — 3 marks.

Chapter 6

Permutations and Combinations — All Formulas

nPr = n!/(n-r)!

nCr = n!/[r!(n-r)!]

nCr = nC(n-r)

Number of ways to arrange n distinct objects in a circle = (n-1)!

💡 Pro-Tip / Memory Trick:

Use Permutation when ORDER matters (arranging), use Combination when order does NOT matter (selecting/choosing) — say 'P for Position, C for Choosing' to instantly pick the right formula.

📝 Most Repeated Board Question Pattern:

Word problems on forming committees, arranging letters of a word, or forming numbers with given digits — 3-5 marks, one of the highest-scoring chapters if practiced well.

Chapter 7

Binomial Theorem — All Formulas

(a+b)ⁿ = Σ nCr aⁿ⁻ʳ bʳ (r from 0 to n)

General term: Tr+1 = nCr aⁿ⁻ʳ bʳ

Number of terms in expansion of (a+b)ⁿ = n+1

💡 Pro-Tip / Memory Trick:

To find the 'middle term,' remember: if n is even there's ONE middle term at position (n/2 + 1); if n is odd there are TWO middle terms — a very commonly tested distinction.

📝 Most Repeated Board Question Pattern:

Find a specific term (like the 5th term or the term containing x⁵) in a binomial expansion using the general term formula — 3 marks.

Chapter 8

Sequences and Series — All Formulas

AP: an = a+(n-1)d, Sn = n/2[2a+(n-1)d]

GP: an = ar^(n-1), Sn = a(rⁿ-1)/(r-1) for r≠1

Sum to infinity of GP (|r|<1): S∞ = a/(1-r)

Arithmetic Mean = (a+b)/2, Geometric Mean = √(ab)

💡 Pro-Tip / Memory Trick:

Sum to infinity ONLY works when |r| < 1 — students often apply it to a GP with r ≥ 1 and get a wrong 'infinite sum' answer where none should exist.

📝 Most Repeated Board Question Pattern:

Find the sum of n terms of an AP or GP, or find AM/GM between two numbers, or solve word problems combining both — 3-5 marks.

Chapter 9

Straight Lines — All Formulas

Slope: m = (y2-y1)/(x2-x1)

Point-slope form: y-y1 = m(x-x1)

Slope-intercept form: y = mx+c

Distance of a point (x1,y1) from line Ax+By+C=0: |Ax1+By1+C|/√(A²+B²)

💡 Pro-Tip / Memory Trick:

To check if two lines are parallel, compare slopes directly (m1=m2); to check perpendicularity, multiply slopes (m1×m2 = -1) — one quick multiplication settles most 'nature of lines' questions.

📝 Most Repeated Board Question Pattern:

Find the equation of a line given a point and slope, or the distance of a point from a line — 2-3 marks.

Chapter 10

Conic Sections — All Formulas

Circle: x²+y² = r² (centre origin), (x-h)²+(y-k)² = r² (centre h,k)

Parabola: y² = 4ax (opens right)

Ellipse: x²/a² + y²/b² = 1 (a>b)

Hyperbola: x²/a² - y²/b² = 1

💡 Pro-Tip / Memory Trick:

Look at the SIGN between the two squared terms to instantly identify the conic: a plus sign with equal denominators is a circle, plus with different denominators is an ellipse, and a minus sign is a hyperbola.

📝 Most Repeated Board Question Pattern:

Find the equation of a circle/parabola/ellipse given specific conditions (centre, radius, focus, vertex) — 3-5 marks.

Chapter 11

Introduction to Three Dimensional Geometry — All Formulas

Distance between two points in 3D: d = √[(x2-x1)²+(y2-y1)²+(z2-z1)²]

Section formula in 3D (internal division): [(mx2+nx1)/(m+n), (my2+ny1)/(m+n), (mz2+nz1)/(m+n)]

💡 Pro-Tip / Memory Trick:

Everything from 2D coordinate geometry simply extends by adding a z-coordinate — if you know the 2D distance/section formula well, this chapter is basically free marks.

📝 Most Repeated Board Question Pattern:

Find the distance between two points in 3D space, or find coordinates of a point dividing a segment in a given ratio — 2-3 marks.

Chapter 12

Limits and Derivatives — All Formulas

d/dx(xⁿ) = nxⁿ⁻¹

d/dx(sin x) = cos x, d/dx(cos x) = -sin x

lim(x→0) sinx/x = 1

Standard limit: lim(x→a) (xⁿ-aⁿ)/(x-a) = naⁿ⁻¹

💡 Pro-Tip / Memory Trick:

When a limit gives 0/0 directly on substitution, that's your signal to factor, rationalise, or use a standard limit formula — never just write '0/0 = undefined' and stop there.

📝 Most Repeated Board Question Pattern:

Evaluate limits using standard formulas, or find the derivative of polynomial/trigonometric functions from first principles — 3-5 marks.

Chapter 13

Statistics — All Formulas

Mean deviation about mean = Σ|xi - x̄| fi / Σfi

Variance (σ²) = Σfi(xi-x̄)² / Σfi

Standard deviation σ = √Variance

💡 Pro-Tip / Memory Trick:

Standard deviation is simply the square root of variance — never report variance as your final answer when the question specifically asks for standard deviation, a very common careless mistake.

📝 Most Repeated Board Question Pattern:

Find the mean deviation, variance, and standard deviation of grouped or ungrouped data — 5 marks, calculation-heavy.

Chapter 14

Probability — All Formulas

P(A) = n(A)/n(S)

P(A∪B) = P(A)+P(B)-P(A∩B)

P(A') = 1 - P(A)

For mutually exclusive events: P(A∪B) = P(A)+P(B)

💡 Pro-Tip / Memory Trick:

Before applying P(A∪B) = P(A)+P(B), always check whether the events are mutually exclusive — if they overlap even slightly, you must subtract P(A∩B), or your final probability will be inflated.

📝 Most Repeated Board Question Pattern:

Find probability using a sample space of dice, cards, or coins, combined with the addition theorem of probability — 3 marks.

⚡ 5-Minute Quick Revision Cheatsheet

High-yield summary — scan this table one last time before you walk into the exam hall.

Chapter	Key Formula	Quick Trick
1. Sets	n(A∪B) = n(A) + n(B) - n(A∩B)	For n(A∪B), think 'add both, minus the overlap you double-counted' — d...
2. Relations and Functions	If n(A)=m, n(B)=n, then n(A×B) = mn	Cartesian product count is just multiplication (m×n) — don't confuse i...
3. Trigonometric Functions	sin²x + cos²x = 1	Whenever you see a sum/difference formula, remember: sin keeps the sam...
4. Complex Numbers and Quadratic Equations	i² = -1	Whenever discriminant D is negative, don't panic and say 'no solution'...
5. Linear Inequalities	If a < b, then a+c < b+c (adding same number preserves inequality)	The ONE rule that decides everything in this chapter: multiplying or d...
6. Permutations and Combinations	nPr = n!/(n-r)!	Use Permutation when ORDER matters (arranging), use Combination when o...
7. Binomial Theorem	(a+b)ⁿ = Σ nCr aⁿ⁻ʳ bʳ (r from 0 to n)	To find the 'middle term,' remember: if n is even there's ONE middle t...
8. Sequences and Series	AP: an = a+(n-1)d, Sn = n/2[2a+(n-1)d]	Sum to infinity ONLY works when \|r\| < 1 — students often apply it t...
9. Straight Lines	Slope: m = (y2-y1)/(x2-x1)	To check if two lines are parallel, compare slopes directly (m1=m2); t...
10. Conic Sections	Circle: x²+y² = r² (centre origin), (x-h)²+(y-k)² = r² (centre h,k)	Look at the SIGN between the two squared terms to instantly identify t...
11. Introduction to Three Dimensional Geometry	Distance between two points in 3D: d = √[(x2-x1)²+(y2-y1)²+(z2-z1)²]	Everything from 2D coordinate geometry simply extends by adding a z-co...
12. Limits and Derivatives	d/dx(xⁿ) = nxⁿ⁻¹	When a limit gives 0/0 directly on substitution, that's your signal to...
13. Statistics	Mean deviation about mean = Σ\|xi - x̄\| fi / Σfi	Standard deviation is simply the square root of variance — never repor...
14. Probability	P(A) = n(A)/n(S)	Before applying P(A∪B) = P(A)+P(B), always check whether the events ar...

⚠️ Common Mistakes to Avoid in the Exam Hall

Sign errors in sum/difference trig formulas — mixing up when to add vs subtract in sin(x+y) and cos(x+y).
Confusing Permutations and Combinations — using nPr when order doesn't matter, or nCr when it does.
Applying sum to infinity of a GP without checking |r| < 1 first — this condition is compulsory.
Forgetting the principal range while evaluating inverse-related or restricted domain questions.
Mixing up variance and standard deviation — reporting variance when the question asks specifically for standard deviation.

❓ FAQs — Class 11 Maths Maths Formulas

How many chapters are there in CBSE Class 11 Maths for 2026-27?

There are 14 chapters in the current CBSE Class 11 Maths syllabus, spread across 5 units — Sets & Functions, Algebra, Coordinate Geometry, Calculus, and Statistics & Probability.

Which Class 11 Maths chapters carry the most weightage?

Trigonometric Functions, Relations and Functions, Complex Numbers, and Sets generally carry maximum marks and also form the base for Class 12 topics.

Is Class 11 Maths harder than Class 10 Maths?

Class 11 Maths introduces more abstract topics like Limits, Derivatives, and Conic Sections, so it can feel tougher initially, but consistent NCERT practice makes it manageable.

How to memorise Class 11 Trigonometry formulas fast?

Focus on the core sum/difference formulas first (sin and cos of x+y), since most other identities can be derived from these instead of memorised separately.

Does Class 11 Maths affect Class 12 board performance?

Yes, significantly — Class 12 topics like Continuity, Integrals, and Vectors build directly on Class 11 concepts like Limits, Trigonometry, and Coordinate Geometry.

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