Class 11 · Mathematics · English medium
Class 11 Mathematics companion
An interactive companion to Class 11 Mathematics: original explanations, graphs and interactive models, step-by-step worked examples and practice with full solutions.
An original companion to Mathematics, NCERT Class 11 Mathematics (2026–27 edition). Official textbook ↗ ncert.nic.in
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Chapters
- ENHinglish
Chapter 1: Sets
The chapter builds the language of sets used through Classes 11 and 12. - ENHinglish
Chapter 2: Relations and Functions
Class 11 introduction to relations and functions. - ENHinglish
Chapter 3: Trigonometric Functions
The chapter treats an angle as an amount of turning, measured in degrees or radians ( rad arc ). - ENHinglish
Chapter 4: Complex Numbers and Quadratic Equations
Complex numbers give negative numbers square roots. - ENHinglish
Chapter 5: Linear Inequalities
Class 11 Maths Chapter 5 (rationalised NCERT) treats linear inequalities in one variable. - ENHinglish
Chapter 6: Permutations and Combinations
NCERT Class 11 Maths Chapter 6 teaches counting without listing. - ENHinglish
Chapter 7: Binomial Theorem
The chapter expands for positive integers . - ENHinglish
Chapter 8: Sequences and Series
Class 11 sequences and series. - ENHinglish
Chapter 9: Straight Lines
Class 11 coordinate geometry of the straight line. - ENHinglish
Chapter 10: Conic Sections
Conic sections are the curves a plane cuts from a double-napped cone: circle, ellipse, parabola and hyperbola, with a point, a line or a pai - ENHinglish
Chapter 11: Introduction to Three Dimensional Geometry (3D Geometry)
Three numbers for every point of space, and the distance between any two - ENHinglish
Chapter 12: Limits and Derivatives
Class 11 introduction to calculus. - ENHinglish
Chapter 13: Statistics
Class 11 statistics: measures of dispersion. - ENHinglish
Chapter 14: Probability
NCERT Class 11 Maths Chapter 14: an event is a subset of a sample space and probability is a function on events.
Also in Hinglish
- Chapter 1: Sets (Hinglish)
- Chapter 2: Relations aur Functions (Hinglish)
- Chapter 3: Trigonometric Functions (Hinglish)
- Chapter 4: Complex Numbers aur Quadratic Equations (Hinglish)
- Chapter 5: Linear Inequalities (Hinglish)
- Chapter 6: Permutations aur Combinations (Hinglish)
- Chapter 7: Binomial Theorem (Hinglish)
- Chapter 8: Sequences aur Series (Hinglish)
- Chapter 9: Straight Lines (Hinglish)
- Chapter 10: Conic Sections (Hinglish)
- Chapter 11: Three Dimensional Geometry ka Introduction (Hinglish)
- Chapter 12: Limits aur Derivatives (Hinglish)
- Chapter 13: Statistics (Hinglish)
- Chapter 14: Probability (Hinglish)
A
addition principleIf the outcomes split into cases that cannot happen together, the total is the sum of the case counts.Ch 6 · Permutations and Combinationsadditive inverseयोज्य प्रतिलोमFor z = a + ib, the number -z = -a - ib; the two add up to 0.Ch 4 · Complex Numbers and Quadratic Equationsallied anglesAngles such as π 2 ± x, π ± x and 2 π - x, whose trigonometric values are those of x up to sign, with sine and cosine swapped at π 2 ± x.Ch 3 · Trigonometric FunctionsangleकोणThe amount of turning that takes a ray from its initial side to its terminal side about the vertex; anticlockwise turns are positive.Ch 3 · Trigonometric FunctionsArgand planeआर्गंड तलA coordinate plane in which the point (a, b) stands for the complex number a + ib.Ch 4 · Complex Numbers and Quadratic Equationsarithmetic meanसमांतर माध्यFor numbers a and b, the number A = a+b 2; then a, A, b is an A.P.Ch 8 · Sequences and Seriesarithmetic progressionसमांतर श्रेढ़ीA sequence in which each term is the previous term plus a fixed common difference d.Ch 8 · Sequences and Seriesassumed meanकल्पित माध्यA convenient value near the middle of the data from which deviations are measured to simplify arithmetic.Ch 13 · Statisticsasymptoteअनंतस्पर्शीA line that a graph approaches ever more closely without meeting it, such as x = π 2 for y = tan x.Ch 3 · Trigonometric FunctionsB
binomialद्विपदAn algebraic expression with exactly two terms, such as a + b or 3x - 2.Ch 7 · Binomial Theorembinomial coefficientद्विपद गुणांकOne of the numbers ⁿ C r that multiply the terms of (a+b)ⁿ.Ch 7 · Binomial Theorembinomial theoremद्विपद प्रमेयThe rule (a+b)ⁿ = ∑r=0ⁿ ⁿ C r a n-rb r for every positive integer n.Ch 7 · Binomial TheoremC
Cartesian productकार्तीय गुणनA × B, the set of all ordered pairs (a, b) with a ∈ A and b ∈ B.Ch 2 · Relations and Functionscentroidकेंद्रकThe common point of a triangle's three medians; its coordinates are the averages of the vertices' coordinates.Ch 11 · Introduction to Three Dimensional Geometrycircleवृत्तThe set of points of a plane at a fixed distance (the radius) from a fixed point (the centre).Ch 10 · Conic Sectionsclass markवर्ग चिह्नThe mid-point of a class interval, used to stand for every observation in that class.Ch 13 · Statisticscodomainसहप्रांतThe set B for a relation or function from A to B.Ch 2 · Relations and FunctionscollinearसंरेखLying on one straight line. Three points are collinear when the triangle they form has zero area.Ch 9 · Straight LinescollinearसंरेखLying on one straight line.Ch 11 · Introduction to Three Dimensional GeometrycombinationसंचयA selection of objects in which order does not matter; ⁿCr counts those of r out of n different objects.Ch 6 · Permutations and CombinationscombinationसंचयA selection of objects in which order does not matter; r objects can be selected from n in ⁿ C r ways.Ch 7 · Binomial Theoremcommon ratioसार्व अनुपातThe constant r = ak+1 ak of a G.P.; it is never 0.Ch 8 · Sequences and SeriescomplementपूरकA', the set of elements of the universal set U that are not in A; so A' = U - A.Ch 1 · Setscomplementary eventपूरक घटनाFor an event A, the event A' = S - A of all outcomes not in A; it occurs exactly when A does not.Ch 14 · Probabilitycomplex numberसम्मिश्र संख्याA number a + ib in which a and b are real and i² = -1.Ch 4 · Complex Numbers and Quadratic Equationscompound eventमिश्र घटनाAn event with more than one sample point.Ch 14 · Probabilityconcurrent linesसंगामी रेखाएँThree or more lines that all pass through one common point.Ch 9 · Straight Linesconic sectionशंकु परिच्छेदA curve where a plane cuts a double cone: a circle, ellipse, parabola or hyperbola.Ch 10 · Conic Sectionsconjugateसंयुग्मीFor z = a + ib, the number z = a - ib, with the sign of the imaginary part reversed.Ch 4 · Complex Numbers and Quadratic Equationscontinuous frequency distributionसतत बारंबारता बंटनA table giving the number of observations in each of a set of class intervals that have no gaps between them.Ch 13 · Statisticscoordinate axesनिर्देशांक अक्षThe three mutually perpendicular lines through the origin, the x -, y - and z -axes, along which coordinates are measured.Ch 11 · Introduction to Three Dimensional Geometrycoordinate planeनिर्देशांक तलA plane containing two of the axes: the XY-, YZ- or ZX-plane.Ch 11 · Introduction to Three Dimensional Geometrycoordinates of a pointनिर्देशांकThe ordered triplet (x, y, z) of signed distances of a point from the YZ-, ZX- and XY-planes.Ch 11 · Introduction to Three Dimensional Geometrycumulative frequencyसंचयी बारंबारताThe running total of the frequencies up to and including a value or class.Ch 13 · StatisticsD
degenerate conicA point, a line or a pair of lines, cut by a plane through the vertex of the cone.Ch 10 · Conic SectionsdegreeअंशOne 360th of a full turn, written 1 °; 1 ° = 60' and 1' = 60''.Ch 3 · Trigonometric Functionsderivativeअवकलजf'(a) = limh→0 f(a + h) - f(a) h, the instantaneous rate of change of f at a and the slope of the tangent there.Ch 12 · Limits and DerivativesdeviationविचलनThe difference x - a between an observation and a fixed value a; it can be positive or negative.Ch 13 · Statisticsdifference of setsसमुच्चयों का अंतरA - B, the set of elements of A that are not in B.Ch 1 · Setsdifference quotientअंतर भागफलf(a + h) - f(a) h, the average rate of change of f between a and a + h; the slope of a chord.Ch 12 · Limits and DerivativesdirectrixनियताThe fixed line in the definition of a parabola.Ch 10 · Conic Sectionsdiscrete frequency distributionअसतत बारंबारता बंटनA table listing each distinct value with the number of times it occurs.Ch 13 · Statisticsdisjoint setsअसंयुक्त समुच्चयSets with no common element, so that A ∩ B = ϕ.Ch 1 · Setsdistance formulaदूरी सूत्रThe rule PQ² = (x2 - x1)² + (y2 - y1)² + (z2 - z1)², where P and Q have coordinates (x1, y1, z1) and (x2, y2, z2).Ch 11 · Introduction to Three Dimensional Geometrydomainप्रांतThe set of first entries of a relation; for a function f: A → B, the whole of A.Ch 2 · Relations and Functionsdouble inequalityA statement that places a quantity between two bounds, such as 40 ≤ m < 60.Ch 5 · Linear InequalitiesE
eccentricityउत्केंद्रताThe ratio e = c/a; below 1 for an ellipse, above 1 for a hyperbola.Ch 10 · Conic Sectionsellipseदीर्घवृत्तThe set of points of a plane whose distances from two foci add up to a constant.Ch 10 · Conic Sectionsempty setरिक्त समुच्चयThe set with no elements, written ϕ or.Ch 1 · Setsequal setsसमान समुच्चयSets with exactly the same elements; order and repetition in a listing do not matter.Ch 1 · Setsequally likely outcomesसम-संभाव्य परिणामOutcomes that all have the same probability, 1 n when there are n of them.Ch 14 · Probabilityeven functionसम फलनA function with f(-x) = f(x) for every x, such as cos x.Ch 3 · Trigonometric FunctionseventघटनाAny subset of the sample space. It occurs when the outcome of the experiment belongs to it.Ch 14 · Probabilityexhaustive eventsनिःशेष घटनाएँEvents whose union is the whole sample space, so at least one of them occurs at every trial.Ch 14 · ProbabilityF
factorialक्रमगुणितn! = 1 × 2 × ⋯ × n for a natural number n, with 0! = 1.Ch 6 · Permutations and Combinationsfactorialक्रमगुणितn! = 1 × 2 × ⋯ × n for a positive integer n, with 0! = 1.Ch 7 · Binomial TheoremFibonacci sequenceThe sequence 1, 1, 2, 3, 5, 8, … in which each term after the second is the sum of the two before it.Ch 8 · Sequences and Seriesfinite setपरिमित समुच्चयA set that is empty or whose elements can be counted with the count ending at a natural number; any other set is infinite.Ch 1 · Setsfirst principleप्रथम सिद्धांतFinding a derivative directly from its definition as a limit of difference quotients.Ch 12 · Limits and DerivativesfocusनाभिA fixed point used to define a conic: a parabola has one focus, an ellipse and a hyperbola have two.Ch 10 · Conic SectionsfunctionफलनA relation from A to B in which every element of A has exactly one image.Ch 2 · Relations and Functionsfundamental principle of countingगणना का आधारभूत सिद्धांतIf one task can be done in m ways and then a second in n ways, the two in order can be done in mn ways.Ch 6 · Permutations and CombinationsG
general linear equationव्यापक रैखिक समीकरणAn equation Ax + By + C = 0, where A, B are not both zero. Every line can be written this way.Ch 9 · Straight Linesgeneral termव्यापक पदA formula for an in terms of the position n, such as an = 4n - 1.Ch 8 · Sequences and SeriesgeneratorA straight line on the surface of a cone through its vertex; turning it about the axis sweeps out the cone.Ch 10 · Conic Sectionsgeometric meanगुणोत्तर माध्यFor positive a and b, the number G = √ ab; then a, G, b is a G.P.Ch 8 · Sequences and Seriesgeometric progressionगुणोत्तर श्रेढ़ीA sequence of non-zero numbers in which each term is the previous term times a fixed common ratio r.Ch 8 · Sequences and Seriesgeometric seriesगुणोत्तर श्रेणीThe series a + ar + ar² + ⋯ formed from a G.P.Ch 8 · Sequences and Seriesgreatest integer functionमहत्तम पूर्णांक फलन[x], the largest integer not exceeding x; for example [2.7] = 2 and [-2.7] = -3.Ch 2 · Relations and FunctionsH
hyperbolaअतिपरवलयThe set of points of a plane whose distances from two foci differ by a constant.Ch 10 · Conic SectionsI
imageप्रतिबिंबIf (a, b) belongs to a relation, b is an image of a; for a function, f(a) is the image of a.Ch 2 · Relations and Functionsimaginary axisकाल्पनिक अक्षThe vertical axis of the Argand plane; its points are the numbers 0 + ib.Ch 4 · Complex Numbers and Quadratic Equationsimaginary partकाल्पनिक भागFor z = a + ib, the real number b (not ib), written Im z.Ch 4 · Complex Numbers and Quadratic Equationsimaginary unitकाल्पनिक इकाईThe number i whose square is -1. It is written √ -1 and read 'iota'.Ch 4 · Complex Numbers and Quadratic Equationsimpossible eventअसंभव घटनाThe empty set ϕ viewed as an event: no outcome makes it occur.Ch 14 · ProbabilityinclinationझुकावThe angle θ from the positive x -axis, turning anticlockwise, to a line; 0 ° ≤ θ < 180 °.Ch 9 · Straight LinesindexघातांकThe power to which an expression is raised; in (a+b)ⁿ the index is n.Ch 7 · Binomial TheoreminequalityअसमिकाA statement that compares two numbers or expressions using <, >, ≤ or ≥.Ch 5 · Linear Inequalitiesinstantaneous rate of changeतात्क्षणिक परिवर्तन दरThe rate at which a quantity is changing at one instant: the number that average rates over shrinking intervals approach.Ch 12 · Limits and DerivativesinterceptअंतःखंडThe coordinate where a line crosses an axis: c if it meets the y -axis at (0, c), d if it meets the x -axis at (d, 0).Ch 9 · Straight Linesintersectionसर्वनिष्ठA ∩ B, the set of elements that belong to both A and B.Ch 1 · SetsintervalअंतरालThe set of all real numbers between two end points, each end point included or excluded, such as [a, b).Ch 1 · SetsintervalअंतरालAn unbroken stretch of the real line, such as (-3, 2] or [4, ∞).Ch 5 · Linear InequalitiesL
latus rectumनाभिलंबThe chord through a focus perpendicular to the axis of the conic.Ch 10 · Conic Sectionsleft-hand limitबाएँ पक्ष की सीमाThe number f(x) approaches as x → a through values less than a, written limx→a⁻ f(x).Ch 12 · Limits and Derivativeslimitसीमाlimx→a f(x) = L: the values f(x) get as close to L as we like when x is close enough to a, with x ≠ a.Ch 12 · Limits and Derivativeslinear inequalityरैखिक असमिकाAn inequality whose two sides are polynomials of degree at most 1 in the variables, such as 3x - 7 < 0 or 2x + 3y ≤ 6.Ch 5 · Linear Inequalitiesliteral inequalityAn inequality containing a variable, such as v ≤ 60; its truth depends on the value of the variable.Ch 5 · Linear InequalitieslocusबिंदुपथThe set of all points that satisfy a given condition; in space it is usually a surface.Ch 11 · Introduction to Three Dimensional GeometryM
major axisदीर्घ अक्षThe longest chord of an ellipse, through both foci; the minor axis is the chord through the centre perpendicular to it.Ch 10 · Conic Sectionsmathematical inductionगणितीय आगमनA way to prove a statement for every positive integer n: prove it for n = 1, then prove that its truth for n = k forces its truth for n = k + 1.Ch 7 · Binomial Theoremmean deviationमाध्य विचलनThe mean of the distances |xi - a| of the observations from a central value a, usually the mean or the median.Ch 13 · Statisticsmeasure of central tendencyकेंद्रीय प्रवृत्ति की मापA single value, such as the mean or the median, around which the data are centred.Ch 13 · Statisticsmeasure of dispersionप्रकीर्णन की मापA number that describes how widely the observations are scattered, such as the range or the standard deviation.Ch 13 · Statisticsmedian classमाध्यिका वर्गThe class in which the cumulative frequency first reaches half the total frequency.Ch 13 · Statisticsmidpointमध्य-बिंदुThe point of a segment that is equally far from its two ends; its coordinates are the averages of theirs.Ch 11 · Introduction to Three Dimensional GeometrymodulusमापांकFor z = a + ib, the non-negative real number |z| = √ a² + b², the distance of z from the origin.Ch 4 · Complex Numbers and Quadratic Equationsmodulus functionमापांक फलन|x|, equal to x for x ≥ 0 and to -x for x < 0.Ch 2 · Relations and Functionsmultiplicative inverseगुणात्मक प्रतिलोमFor z ≠ 0, the number z⁻¹ with z z⁻¹ = 1. It equals z/|z|².Ch 4 · Complex Numbers and Quadratic Equationsmutually exclusive eventsपरस्पर अपवर्जी घटनाएँEvents that cannot occur together: A ∩ B = ϕ.Ch 14 · ProbabilityN
nappeEither of the two halves of a double cone that meet at the vertex.Ch 10 · Conic Sectionsnumerical inequalityAn inequality between numbers only, such as -5 < -2; it is simply true or false.Ch 5 · Linear InequalitiesO
octantअष्टांशOne of the eight regions into which the three coordinate planes divide space.Ch 11 · Introduction to Three Dimensional Geometryodd functionविषम फलनA function with f(-x) = -f(x) for every x, such as sin x and tan x.Ch 3 · Trigonometric Functionsordered pairक्रमित युग्मA pair (a, b) in which order matters: (a, b) = (c, d) only when a = c and b = d.Ch 2 · Relations and Functionsoriginमूल बिंदुThe point O where the three axes meet; its coordinates are (0, 0, 0).Ch 11 · Introduction to Three Dimensional GeometryP
parabolaपरवलयThe set of points of a plane equally far from a fixed point (the focus) and a fixed line (the directrix).Ch 10 · Conic SectionsPascal's ruleⁿCr + ⁿCr-1 = ⁿ⁺¹Cr: each inner entry of Pascal's triangle is the sum of the two above it.Ch 6 · Permutations and CombinationsPascal's ruleThe identity ⁿ C r + ⁿ C r-1 = ⁿ⁺¹ C r for 1 ≤ r ≤ n.Ch 7 · Binomial TheoremPascal's triangleपास्कल त्रिभुजA triangular array with 1 at both ends of each row and every inside entry the sum of the two above it; row n lists ⁿ C 0, …, ⁿ C n.Ch 7 · Binomial Theoremperiodic functionआवर्ती फलनA function with f(x + p) = f(x) for all x, for some fixed p > 0; the least such p is the period.Ch 3 · Trigonometric Functionspermutationक्रमचयAn arrangement of some or all of a set of objects in a definite order; ⁿPr counts those of r out of n different objects.Ch 6 · Permutations and Combinationsperpendicular distanceलंबवत दूरीHow far a point is from a line, measured along the perpendicular dropped to it, which is the shortest route.Ch 9 · Straight Linespolynomial functionबहुपद फलनa0 + a1 x + … + an xⁿ with real coefficients and whole-number powers.Ch 2 · Relations and Functionsprobabilityप्रायिकताA function P that gives each event a number P(E) with P(E) ≥ 0, P(S) = 1 and P(E ∪ F) = P(E) + P(F) for mutually exclusive E, F.Ch 14 · Probabilityproduct ruleगुणनफल नियम(uv)' = u'v + uv', also called the Leibniz rule.Ch 12 · Limits and Derivativesproper subsetउचित उपसमुच्चयA subset A of B with A ≠ B, so that B has at least one element outside A.Ch 1 · Setspurely imaginary numberशुद्ध काल्पनिक संख्याA complex number 0 + ib with b ≠ 0, such as 7i.Ch 4 · Complex Numbers and Quadratic EquationsQ
quadrantal angleAn angle that is a whole-number multiple of π 2, so that its terminal side lies along an axis.Ch 3 · Trigonometric Functionsquotient ruleभागफल नियम(u v)' = u'v - uv' v² wherever v ≠ 0.Ch 12 · Limits and DerivativesR
radianरेडियनThe angle at the centre of a circle cut off by an arc as long as the radius; a full turn is 2 π radians.Ch 3 · Trigonometric Functionsrandom experimentयादृच्छिक परीक्षणAn experiment with more than one possible outcome, all known in advance, whose actual outcome cannot be predicted.Ch 14 · ProbabilityrangeपरिसरThe set of all images; it is always a subset of the codomain.Ch 2 · Relations and FunctionsrangeपरिसरLargest observation minus smallest observation.Ch 13 · Statisticsrational functionपरिमेय फलनA quotient p(x) q(x) of polynomial functions, defined where q(x) ≠ 0.Ch 2 · Relations and Functionsrational functionपरिमेय फलनA quotient g(x) h(x) of two polynomials, defined where h(x) ≠ 0.Ch 12 · Limits and Derivativesreal axisवास्तविक अक्षThe horizontal axis of the Argand plane; its points are the real numbers a + 0i.Ch 4 · Complex Numbers and Quadratic Equationsreal functionवास्तविक फलनA function whose domain and range are subsets of R.Ch 2 · Relations and Functionsreal partवास्तविक भागFor z = a + ib, the real number a, written Re z.Ch 4 · Complex Numbers and Quadratic Equationsrectangular coordinate systemThe origin together with three mutually perpendicular axes and the three coordinate planes they determine.Ch 11 · Introduction to Three Dimensional Geometryrectangular parallelepipedघनाभA solid bounded by six rectangular faces, like a brick or a closed carton.Ch 11 · Introduction to Three Dimensional Geometryrecurrence relationA rule that builds each term from earlier terms, given together with the first term or terms.Ch 8 · Sequences and SeriesrelationसंबंधA subset of A × B, usually chosen by a rule linking first and second entries.Ch 2 · Relations and Functionsright-hand limitदाएँ पक्ष की सीमाThe number f(x) approaches as x → a through values greater than a, written limx→a⁺ f(x).Ch 12 · Limits and Derivativesroster formरोस्टर रूपA description of a set that lists its elements, separated by commas, inside braces, as in 2, 4, 6.Ch 1 · SetsS
sample spaceप्रतिदर्श समष्टिThe set S of all possible outcomes of a random experiment; each element is a sample point.Ch 14 · Probabilitysandwich theoremसैंडविच प्रमेयIf f ≤ g ≤ h near a and f and h both tend to l, then g also tends to l.Ch 12 · Limits and Derivativessequenceअनुक्रमA list of numbers in a definite order; formally a function defined on N or on 1, 2, …, k.Ch 8 · Sequences and Seriesseriesश्रेणीThe expression a1 + a2 + a3 + ⋯ formed by adding the terms of a sequence; its sum is the number obtained.Ch 8 · Sequences and Seriessetसमुच्चयA well-defined collection of objects, called its elements: for any object it is certain whether it belongs.Ch 1 · Setsset-builder formसमुच्चय निर्माण रूपA description of a set by a property its elements share, as in x: x ∈ N, x < 4.Ch 1 · Setssigma notationसिग्मा संकेतनA compact way to write a sum: ∑r=0ⁿ f(r) means f(0) + f(1) + ⋯ + f(n).Ch 7 · Binomial Theoremsigma notationShort form for a sum: ∑k=1ⁿ ak means a1 + a2 + ⋯ + an.Ch 8 · Sequences and Seriessignum functionचिह्न फलनsgn x: 1 for x > 0, 0 at x = 0, -1 for x < 0.Ch 2 · Relations and Functionssimple eventसरल घटनाAn event with exactly one sample point, such as 5; also called an elementary event.Ch 14 · Probabilityslack inequalityAn inequality using ≤ or ≥, so the boundary value is allowed.Ch 5 · Linear Inequalitiesslopeढालm = tan θ for a line of inclination θ ≠ 90 °; equal to rise over run between two of its points.Ch 9 · Straight LinessolutionहलA value of the variable that makes the inequality a true statement.Ch 5 · Linear Inequalitiessolution setहल समुच्चयThe set of all solutions of an inequality from the allowed values of the variable.Ch 5 · Linear Inequalitiesstandard deviationमानक विचलनThe positive square root of the variance, written σ; it has the units of the data.Ch 13 · Statisticsstep deviationपद विचलनA deviation from the assumed mean divided by a common factor h: d = x - a h.Ch 13 · Statisticsstrict inequalityAn inequality using < or >, so the boundary value is not allowed.Ch 5 · Linear Inequalitiessubsetउपसमुच्चयA ⊂ B when each member of A belongs to B as well.Ch 1 · Setssum-to-product formulasFormulas that turn a sum or difference of two sines or cosines into a product, such as cos x + cos y = 2 cos x+y 2 cos x-y 2.Ch 3 · Trigonometric Functionssure eventनिश्चित घटनाThe whole sample space S viewed as an event: it occurs at every trial.Ch 14 · Probabilitysystem of inequalitiesTwo or more inequalities that must hold at the same time; its solutions are the values common to all of them.Ch 5 · Linear InequalitiesT
tangentस्पर्श रेखाThe line that just touches a curve at a point; the limiting position of the chords through that point.Ch 12 · Limits and DerivativestermपदOne number of a sequence; an is the term in position n.Ch 8 · Sequences and Seriestransverse axisअनुप्रस्थ अक्षThe axis of a hyperbola through its foci; the conjugate axis is perpendicular to it through the centre.Ch 10 · Conic Sectionstree diagramवृक्ष आरेखA branching picture of successive choices in which each path from the start to a leaf is one outcome.Ch 6 · Permutations and Combinationstrigonometric functionत्रिकोणमितीय फलनA function such as sin x or cos x of a real number x, read from the point at arc length x on the unit circle.Ch 3 · Trigonometric Functionstrigonometric identityत्रिकोणमितीय सर्वसमिकाAn equation in trigonometric functions that is true for every value of the variable at which both sides are defined.Ch 3 · Trigonometric FunctionsU
unionसम्मिलनA ∪ B, the set of elements in A or in B or in both.Ch 1 · Setsunit circleएकक वृत्तThe circle of radius 1 with its centre at the origin.Ch 3 · Trigonometric Functionsuniversal setसार्वत्रिक समुच्चयThe set U that contains every set under discussion in a given context.Ch 1 · SetsV
varianceप्रसरणThe mean of the squared deviations from the mean, written σ².Ch 13 · StatisticsVenn diagramवेन आरेखA picture of sets: a rectangle for the universal set and closed curves, usually circles, for its subsets.Ch 1 · Setsvertexशीर्षA point where a conic meets its axis through the focus or foci.Ch 10 · Conic Sectionsncert.ai is an independent learning companion aligned to the NCERT curriculum. It is not affiliated with or endorsed by NCERT.