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Mathematics • Class 11

Relations and Functions - Class 11

Master Functions & Relations through focused practice that strengthens conceptual understanding, problem-solving skills, and the ability to recognize common traps and misconceptions. Explore challenging questions designed to develop deeper reasoning and confident application of key ideas.

Overview

This chapter covers the fundamentals of Relations and Functions, including types of relations, domain, range, and types of functions. Gain insights into their mathematical significance and practical applications.

Why This Chapter Matters

  • Relations and Functions are pivotal concepts in mathematics, laying the groundwork for topics like calculus, algebra, and discrete mathematics. Understanding these concepts is essential for solving complex mathematical problems.

Real-Life Applications

  • Analyzing and modeling real-world problems in economics and physics.
  • Understanding and designing algorithms in computer science.
  • Building the foundation for higher-level mathematical studies.

Skills You Will Learn

  • Identifying and analyzing relations and functions.
  • Understanding the domain, range, and types of functions.
  • Applying concepts of relations and functions in problem-solving.

Core Concepts to Master

Ordered Pair Equality

Equality (a,b)=(c,d) implies a=c and b=d; fundamental for solving simultaneous equations involving sets.

Cartesian Product Cardinality

If n(A)=p and n(B)=q, then n(AxB)=pq. Trap: Ignoring empty sets resulting in null product.

Relation as Subset

A relation is any subset of AxB. Trap: Forgetting the empty relation and the universal relation.

Domain and Range Nuance

Domain is the set of all first elements; Range is the set of all *actually mapped* second elements.

Total Number of Relations

If n(A)=m, n(B)=n, total relations = 2^(mn). Crucial for permutation-based combinatorics questions.

Function Definition (The 'One-to-One' Constraint)

Each element in domain must have exactly one unique image. Trap: One input mapping to two outputs.

Codomain vs Range Distinction

Range is a subset of codomain. Function definition remains valid even if codomain exceeds range.

Real-Valued Function Domain

Denominator cannot be zero, square root radicand must be non-negative, log argument must be positive.

Identity Function Behavior

f(x)=x. Maps every element to itself; essential for understanding functional identity properties.

Constant Function Logic

f(x)=c for all x. Graph is a horizontal line; zero rate of change.

Polynomial Function Parity

Even degree vs odd degree behavior. Focus on global extrema and end-behavior characteristics.

Rational Function Asymptotes

Identifying vertical asymptotes where denominator vanishes and horizontal asymptotes via limit at infinity.

Modulus Function Symmetry

f(x)=|x|. V-shaped graph; non-differentiable at x=0. Use piecewise definition for all analytical proofs.

Signum Function Discontinuity

f(x)=sgn(x) is 1, 0, or -1. Discontinuous at x=0; essential for inequality testing.

Greatest Integer Function (GIF)

f(x)=[x]. Step function behavior; jumps at every integer. Trap: Precision errors in range calculation.

Algebra of Functions

(f±g)(x) = f(x)±g(x). Domain is intersection of domain f and domain g. Trap: Division by zero.

Concept Collisions Used by Examiners

Competitive examinations rarely assess concepts in isolation. Instead, examiners intentionally combine multiple concepts from this and related chapters to create higher-order questions that test conceptual reasoning, analytical thinking, and problem-solving ability. The concept collision patterns below represent the combinations most frequently used while designing questions for this chapter.

Ordered Pair Equality
Algebraic Manipulation of i
Geometrical Interpretation of Modulus
Ordered Pair Equality
Area of Triangle via Determinants
Condition of Collinearity
Ordered Pair Equality
Greatest Integer Function (GIF)
Greatest Integer Function Traps
System of Inequalities
Ordered Pair Equality
Partial Fractions Decomposition
Binomial Theorem for Negative/Fractional Indices
Ordered Pair Equality
System of Linear Equations (Cramer/Inverse)
Minors and Cofactors Sign Convention
Cartesian Product Cardinality
Bijectivity and Inverse
Composition Inverse Identity Traps
Signum Function Discontinuity
Cartesian Product Cardinality
Locus Problems via Transformation
Distance from point to plane
Modulus Inequality Logic
Cartesian Product Cardinality
Sample Space Partitioning
Conditional Probability Foundations
Complementary Counting
Cartesian Product Cardinality
Total Selection (at least one)
Even Multiplicity Roots
Complementary Counting
Relation as Subset
Derangements (Inclusion-Exclusion)
Complementary Counting
Relation as Subset
Factor Theorem in Determinants
Row/Column Exchange Parity
Relation as Subset
Homogeneous Function Homogeneity
Implicit Differentiation Rate
Domain and Range Nuance
Completing the Square in Quadratics
Triangle Inequality Mind Games
Domain and Range Nuance
Composition Continuity
Step Function Discontinuities
Domain and Range Nuance
General Equation Transformations
Signum Function Discontinuity
Domain and Range Nuance
Increasing/Decreasing Strictness
First Derivative Test Trap
Total Number of Relations
Derangements (Inclusion-Exclusion)
Geometry-based Combinations
Total Number of Relations
Real-Valued Function Domain
Modulus Function Breakdown
Domain Constraint Intersections
Total Number of Relations
Sigma Notation Properties
Expansion of Products of Binomials
Function Definition (The 'One-to-One' Constraint)
Bijectivity and Inverse
Even and Odd Function Symmetry
Function Definition (The 'One-to-One' Constraint)
Geometry-based Combinations
Step Function Discontinuities
Function Definition (The 'One-to-One' Constraint)
Indeterminate Forms
Modulus Sign Dependency
Function Definition (The 'One-to-One' Constraint)
Singular vs Non-Singular Matrices
Minors and Cofactors Sign Convention
Function Definition (The 'One-to-One' Constraint)
Variable Separable Constraints
Implicit Differentiation Implicit Domain
Codomain vs Range Distinction
Bijectivity and Inverse
The Modulus Trap
Codomain vs Range Distinction
Boundary Value Theorem
Corner Point Method Precision
Codomain vs Range Distinction
Domain Constraint Intersections
The Sum-Difference Formula Constraints
Cross Multiplication Trap
Codomain vs Range Distinction
Infinite Limit Behavior
Second Derivative Test Limitations
Codomain vs Range Distinction
Inverse Existence Criterion
Differentiability vs Continuity
Real-Valued Function Domain
Indeterminate Forms
The Zero-Factor Cancellation Trap
Real-Valued Function Domain
Logarithmic Differentiation Domain
Modulus Function Breakdown
Real-Valued Function Domain
Newton-Leibniz Formula with variable limits
Greatest Integer Function Traps
Compound Function Boundaries
Real-Valued Function Domain
Parametric form pitfalls
Symmetric vs Non-symmetric form
Real-Valued Function Domain
The Sum-Difference Formula Constraints
Closed vs Open Intervals
Identity Function Behavior
Geometry Constraint Modeling
Concavity Analysis
Chain Rule Inner Function Differentiability
Identity Function Behavior
Injective Mapping (One-One)
The Zero-Factor Cancellation Trap
Domain Constraint Intersections
Identity Function Behavior
Inversion and Determinant Product
Singular vs. Non-Singular Threshold
Adjoint-Determinant Relationship
Identity Function Behavior
Substitution Logic in Homogeneous DE
The Modulus Trap
L'Hopital's Pitfall
Constant Function Logic
Domain Constraint Intersections
Greatest Integer Function (GIF)
Constant Function Logic
Rolle's Theorem Anchors
Non-Differentiable Extrema
Polynomial Function Parity
Coefficient of x^r in Expansion
Term Independent of x
Polynomial Function Parity
Extraneous Solution Rejection
The Quadrant Adjustment Logic
Polynomial Function Parity
Factor Theorem in Determinants
Elementary Row Operation Invariance
Modulus Function Breakdown
Polynomial Function Parity
Homogeneous Function Homogeneity
Implicit to Explicit Conversion
Polynomial Function Parity
Squeeze Theorem (Sandwich Theorem)
Parametric Derivative Endpoint Trap
Rational Function Asymptotes
Cramer's Rule Constraints
Singular vs Non-Singular Matrices
Rational Function Asymptotes
Implicit to Explicit Conversion
Rolle's Theorem Anchors
Rational Function Asymptotes
Increasing/Decreasing Strictness
Greatest Integer Function (GIF)
Rational Function Asymptotes
Indeterminate Forms
Geometrical Interpretation of Modulus
Rational Function Asymptotes
Integrating Factor (IF) Sign Sensitivity
Signum Function Discontinuity
Modulus Function Symmetry
Linear Differential Equation Structure
Integration Constant Trap
Modulus Function Symmetry
Rolle's Theorem Anchors
Second Derivative Test Limitations
Modulus Function Symmetry
Symmetric and Skew-Symmetric Decomposition
Determinant Product Rule
Modulus Function Symmetry
Wavy Curve (Method of Intervals)
L'Hopital's Pitfall
Signum Function Discontinuity
Global Extrema on Intervals
Second Derivative Test Limitations
Signum Function Discontinuity
Implicit to Explicit Conversion
Extraneous Solution Rejection
Signum Function Discontinuity
Integrating f(x) + xf'(x) forms
Indeterminate Forms
Signum Function Discontinuity
Nilpotent Matrix Logic
Cramer's Rule Constraints
Signum Function Discontinuity
Rolle's Theorem Root Existence
Geometrical Interpretation of Modulus
Greatest Integer Function (GIF)
Composition Continuity
Composition Non-Commutativity
Greatest Integer Function (GIF)
Inequalities in Definite Integrals
Greatest Integer Function Traps
Greatest Integer Function (GIF)
Leibniz Rule for Differentiation under Integral
Rate of Change Dependency
Greatest Integer Function (GIF)
Maximum/Minimum of Quadratic Expressions
Cross Multiplication Trap
Greatest Integer Function (GIF)
Squeeze Theorem (Sandwich Theorem)
Step Function Discontinuities
Algebra of Functions
Differentiation of Determinants
Modulus Function Breakdown
Algebra of Functions
Linear Independence vs Dependence
Matrix Multiplication Non-Commutativity
Algebra of Functions
Mean Value Theorem Applicability
The L'Hôpital's Rule Misuse
Algebra of Functions
Newton-Leibniz Formula with variable limits
Integral Part and Fractional Part
Algebra of Functions
Sigma Notation Properties
Modulus Sign Dependency

Exam Coverage

Understand how this chapter is tested across major competitive examinations.

JEE Advanced

India · Competitive Exam · Undergraduate

JEE Main

India · Competitive Exam · Undergraduate

BITSAT

India · Competitive Exam · Undergraduate

IISER Aptitude Test (IAT)

India · Competitive Exam · Undergraduate

NEST

India · Competitive Exam · Undergraduate

ISI Admission Test

India · Competitive Exam · Undergraduate

CMI Entrance

India · Competitive Exam · Undergraduate

IOQM / INMO

India · Olympiad · High School

SAT Math

United States · Curriculum · High School

A-Level Mathematics

United Kingdom · Curriculum · Advanced Level

A-Level Further Mathematics

United Kingdom · Curriculum · Advanced Level

IB Mathematics AA HL

International · Curriculum · IB Diploma

Singapore A-Level Mathematics

Singapore · Curriculum · Advanced Level

Cambridge International A-Level Mathematics

International · Curriculum · Cambridge

International Mathematical Olympiad (IMO)

International · Olympiad · International

Practice Questions

Strengthen your understanding by solving carefully selected questions from this chapter.

50 Questions
1

Let AA be a 3×33 \times 3 matrix with real entries such that det⁡(A)>0\det(A) > 0. The matrix of minors of AA is given by M=(−24−20−5−18−15−4541)M = \begin{pmatrix} -24 & -20 & -5 \\ -18 & -15 & -4 \\ 5 & 4 & 1 \end{pmatrix} If the ordered triple (x,y,z)(x, y, z) satisfies the matrix equation (xyz)A=(1−12)\begin{pmatrix} x & y & z \end{pmatrix} A = \begin{pmatrix} 1 & -1 & 2 \end{pmatrix} then the value of x+y+zx + y + z is:

2

Let RR be the region in the xyxy-plane defined by the set of points (x,y)(x, y) that satisfy the following conditions: 0≤x≤640 \le x \le 64 0≤y≤640 \le y \le 64 [x+y]−[x−y]=2[y][x+y] - [x-y] = 2[y] where [t][t] denotes the greatest integer less than or equal to tt. Find the area of the region RR.

3

Let t1,t2,t3t_1, t_2, t_3 be the three distinct real roots of the equation t3−10t2+29t−22=0t^3 - 10t^2 + 29t - 22 = 0. For i=1,2,3i = 1, 2, 3, let Pi(xi,yi)P_i(x_i, y_i) be points in the Cartesian plane such that the ordered pairs (xi,yi)(x_i, y_i) satisfy the equality: (xi+2yi,2xi−yi)=(7ti3−7ti2+7ti−4,−ti3+ti2−ti+2)(x_i + 2y_i, 2x_i - y_i) = (7t_i^3 - 7t_i^2 + 7t_i - 4, -t_i^3 + t_i^2 - t_i + 2) Let Δ\Delta be the area of the triangle formed by the points P1,P2,P_1, P_2, and P3P_3. The value of Δ\Delta is:

4

Let f(x)=Px+Q2x2−5x+2f(x) = \frac{Px + Q}{2x^2 - 5x + 2} be expressed as a series expansion f(x)=∑n=0∞anxn+∑n=1∞bnx−nf(x) = \sum_{n=0}^{\infty} a_n x^n + \sum_{n=1}^{\infty} b_n x^{-n} valid in the region 12<∣x∣<2\frac{1}{2} < |x| < 2. If a2=−1a_2 = -1 and b2=1b_2 = 1, find the ordered pair (P,Q)(P, Q).

5

Let S={1,2,3,4,5,6}S = \{1, 2, 3, 4, 5, 6\} and A={1,2,3}A = \{1, 2, 3\}. A function f:A→Sf: A \to S is chosen at random. Given that f(1)≠f(3)f(1) \neq f(3) and there exists at least one x∈Ax \in A such that f(x)≠xf(x) \neq x, what is the probability that f(x)≠xf(x) \neq x for all x∈Ax \in A?

6

Let A={z∈Z[i]∣∣z∣2≤5}A = \{ z \in \mathbb{Z}[i] \mid |z|^2 \le 5 \} and B={w∈Z[i]∣∣w∣2≤5}B = \{ w \in \mathbb{Z}[i] \mid |w|^2 \le 5 \}, where Z[i]\mathbb{Z}[i] denotes the set of Gaussian integers. Let SS be the subset of the Cartesian product A×BA \times B defined by: S={(z,w)∈A×B∣Im(z)=Re(w) and d(P,Π)≤13}S = \left\{ (z, w) \in A \times B \mid \text{Im}(z) = \text{Re}(w) \text{ and } d(P, \Pi) \le \frac{1}{\sqrt{3}} \right\} where d(P,Π)d(P, \Pi) is the perpendicular distance from the point P(Re(z),Im(z),Im(w))P(\text{Re}(z), \text{Im}(z), \text{Im}(w)) to the plane Π:x+y+z=1\Pi: x+y+z=1. Find the cardinality of SS.

7

Let SS be the set of all 4×44 \times 4 matrices with real entries. For any matrix M∈SM \in S, let M∗M^* be the matrix obtained by shifting the rows of MM cyclically downwards by one position (i.e., the ii-th row of MM becomes the (i+1)(i+1)-th row of M∗M^* for i=1,2,3i=1,2,3, and the 44-th row of MM becomes the 11-st row of M∗M^*). A relation RR is defined on SS such that for A,B∈SA, B \in S, A R BA \ R \ B if and only if det⁡(A+B∗)=0\det(A + B^*) = 0. Which of the following statements is true regarding the relation RR?

8

Let S={1,2,3,4,5,6}S = \{1, 2, 3, 4, 5, 6\}. Let NN be the number of relations RR on SS satisfying the following conditions: (i) RR is a bijective function from SS to SS. (ii) R∩R−1=∅R \cap R^{-1} = \emptyset, where R−1={(y,x)∣(x,y)∈R}R^{-1} = \{(y, x) \mid (x, y) \in R\}. Find the value of NN.

9

Let SS be the set of all differentiable functions f:(1,∞)→(1,∞)f: (1, \infty) \to (1, \infty). A relation RR on SS is defined as (f,g)∈R(f, g) \in R if for every homogeneous function H(x,y)H(x, y) of degree k>0k > 0 (where H(x,y)>1H(x, y) > 1), the composite function U(x,y)=f(g(H(x,y)))U(x, y) = f(g(H(x, y))) satisfies the partial differential equation: x∂U∂x+y∂U∂y=2kUln⁡Ux \frac{\partial U}{\partial x} + y \frac{\partial U}{\partial y} = 2k U \ln U It is given that (f,g)∈R(f, g) \in R and (g,h)∈R(g, h) \in R. If g(x)=ex2g(x) = e^{x^2}, h(x)=2xh(x) = 2x, and f(e)=e3f(e) = e^3, what is the value of f(h(2))f(h(2))?

10

Let f(x)=1[x]2−3[x]+2f(x) = \frac{1}{\sqrt{[x]^2 - 3[x] + 2}} and g(x)=12x2+2x+5g(x) = \frac{12}{x^2 + 2x + 5}, where [⋅][ \cdot ] denotes the greatest integer function. Let DD be the domain of the composite function h(x)=f(g(x))h(x) = f(g(x)). Find the sum of all integers that do NOT belong to DD.

11

Let f:R→Rf: \mathbb{R} \to \mathbb{R} be defined as f(x)=(∣x−1∣−3)e−∣x∣f(x) = (|x-1| - 3) e^{-|x|}. The range of f(x)f(x) is:

12

Let SS be the set of all integers in the domain of the real-valued function f(x)=sin⁡−1(∣x2−9x+20∣+∣x2−9x+18∣2)+ln⁡(x−3)+ln⁡(6−x)f(x) = \sin^{-1}\left(\frac{|x^2 - 9x + 20| + |x^2 - 9x + 18|}{2}\right) + \ln(x-3) + \ln(6-x) The total number of relations that can be defined on the set SS is:

13

Let S={−3,−2,−1,0,1,2,3}S = \{-3, -2, -1, 0, 1, 2, 3\}. A relation RR on SS is defined such that it represents a bijective function f:S→Sf: S \to S (i.e., R={(x,f(x))∣x∈S}R = \{(x, f(x)) \mid x \in S\}). Find the total number of such relations RR where no element (x,y)∈R(x, y) \in R satisfies y=xy = x or y=−xy = -x.

14

Let AA be a set containing nn elements, where nn is the number of distinct terms in the expansion of (x+y+z)4(x−y+z)4(x + y + z)^4 (x - y + z)^4. If the total number of reflexive relations on set AA is 2k2^k, then the value of kk is:

15

Let AA be the set of all points (x,y)(x, y) in the xyxy-plane satisfying the equations x2+y2=25x^2 + y^2 = 25 and xy=12xy = 12. Let BB be the range of the function f(t)=[12t2−2t+4]f(t) = \left[ \frac{12}{t^2 - 2t + 4} \right] for t∈Rt \in \mathbb{R}, where [⋅][ \cdot ] denotes the greatest integer function. Find the number of injective mappings from AA to BB.

16

Let f:[−1,1]→Rf: [-1, 1] \to \mathbb{R} be defined by f(x)=∫0xln⁡(t+t2+1)dtf(x) = \int_0^x \ln\left(t + \sqrt{t^2+1}\right) dt Which of the following represents the value of f−1(1−2+ln⁡(1+2))f^{-1}\left( 1 - \sqrt{2} + \ln(1 + \sqrt{2}) \right)?

17

Let y=f(x)y = f(x) be a real-valued function defined on its maximal domain D⊂RD \subset \mathbb{R} such that ff is continuous on DD, differentiable on the interior of DD, and satisfies the equation y3−x3=3(y−x)y^3 - x^3 = 3(y - x) for all x∈Dx \in D. If f(0)=3f(0) = \sqrt{3}, let I⊆DI \subseteq D be the largest interval containing x=0x = 0 such that the restriction of ff to II is a one-to-one function. What is the length of the interval II?

18

Let f:[k,5]→[−5,54]f: [k, 5] \to \left[-5, \frac{5}{4}\right] be a bijective function defined by f(x)=∣x2−6x+5∣−xf(x) = |x^2 - 6x + 5| - x. If g(x)g(x) is the inverse function of f(x)f(x), find the value of g(−1)+g′(−1)g(-1) + g'(-1).

19

Let S={(x,y)∈R2∣y−x≤1,  x+y<5,  x>0,  y≥0}S = \{ (x,y) \in \mathbb{R}^2 \mid y - x \le 1, \; x + y < 5, \; x > 0, \; y \ge 0 \}. Let f:S→Rf: S \to \mathbb{R} be a function defined by f(x,y)=x−yf(x,y) = x - y. If EE represents the range of ff on the domain SS, then EE is equal to:

20

Let F(x)=∫xx2dt3−∣[t]∣F(x) = \int_{x}^{x^2} \frac{dt}{\sqrt{3 - |[t]|}}, where [t][t] denotes the greatest integer less than or equal to tt. Let DD be the maximal domain of F(x)F(x) in R\mathbb{R}, and SS be the set of points in DD where F(x)F(x) is not differentiable. Find the number of elements in SS.

21

Let SS be the set of all integers in the domain of the real-valued function f(x)=25−x2ln⁡(∣x3−3x2−4x+12∣)+ln⁡(∣x2−x−2∣)f(x) = \frac{\sqrt{25 - x^2}}{\ln(|x^3 - 3x^2 - 4x + 12|)} + \ln(|x^2 - x - 2|). Find the sum of all elements in SS.

22

The coordinates (x,y,z)(x, y, z) of a point on a line LL are given by the relation: 3x−62=2−y3=2z−44=t\frac{3x - 6}{2} = \frac{2 - y}{3} = \frac{2z - 4}{4} = t where t∈Rt \in \mathbb{R} is a parameter. A real-valued function ff is defined as: f(t)=sin⁡−1(x+y+z−62)+4−t+t+10f(t) = \sin^{-1}\left( \frac{x + y + z - 6}{2} \right) + \sqrt{4 - t} + \sqrt{t + 10} If the domain of f(t)f(t) is the interval [a,b][a, b], find the value of a2+b2a^2 + b^2.

23

Let y:(0,∞)→Ry: (0, \infty) \to \mathbb{R} be a differentiable function such that y(x)≠xy(x) \neq x for all x≠1x \neq 1, y(1)=1y(1) = 1, and xdydx=y+161x∣yx−1∣297298x \frac{dy}{dx} = y + 161 x \left| \frac{y}{x} - 1 \right|^{\frac{297}{298}} for all x>0x > 0. If y(e)>ey(e) > e and y(1/e)<1/ey(1/e) < 1/e, evaluate the limit: lim⁡x→1y(x)−x(x−1)298\lim_{x \to 1} \frac{y(x) - x}{(x-1)^{298}}

24

Let A=(1−1221−14−13)A = \begin{pmatrix} 1 & -1 & 2 \\ 2 & 1 & -1 \\ 4 & -1 & 3 \end{pmatrix} and M(x)=A+xIM(x) = A + x I for x∈Rx \in \mathbb{R}, where II is the 3×33 \times 3 identity matrix. Let P(x)P(x) be a matrix such that M(x)P(x)=IM(x) P(x) = I for all x>0x > 0. Evaluate the limit: lim⁡x→0+1xdet⁡(I−AP(x))\lim_{x \to 0^+} \frac{1}{x} \det(I - A P(x))

25

Let f:R→Rf: \mathbb{R} \to \mathbb{R} be defined by f(x)=6x−x2f(x) = 6x - x^2. A geometric constraint function is defined as D(x)=∣f(x)−x∣D(x) = |f(x) - x|, representing the vertical distance to the identity line. Let H(x)=D(D(x))H(x) = D(D(x)). Let SS be the set of all real numbers xx where H(x)H(x) is not differentiable. Find the sum of the squares of the elements in SS.

26

Let f(x)=1−sin⁡2x+1+sin⁡2xf(x) = \sqrt{1 - \sin 2x} + \sqrt{1 + \sin 2x} for x∈[0,π2]x \in \left[0, \frac{\pi}{2}\right]. Let SS be the set of all points c∈(0,π2)c \in \left(0, \frac{\pi}{2}\right) such that f′(c)=f(π/2)−f(0)π/2−0f'(c) = \frac{f(\pi/2) - f(0)}{\pi/2 - 0}. Find the number of elements in SS.

27

Let f(x)=cos⁡−1(1−x21+x2)+csc⁡−1(1+x22x)f(x) = \cos^{-1}\left( \frac{1-x^2}{1+x^2} \right) + \csc^{-1}\left( \frac{1+x^2}{2x} \right) for x>0x > 0. Evaluate the integral: I=∫03f(x)[x] dxI = \int_{0}^{\sqrt{3}} f(x) [x] \,dx where [t][t] denotes the greatest integer less than or equal to tt.

28

Let f(x)=∣x2+x2−2x2−x21x3+xx2−2xx3−xx22−3−41∣f(x) = \begin{vmatrix} x^2 + \sqrt{x^2} - 2 & x^2 - \sqrt{x^2} & 1 \\ x^3 + x\sqrt{x^2} - 2x & x^3 - x\sqrt{x^2} & 2 \\ -3 & -4 & 1 \end{vmatrix}.

If SS is the sum of the squares of all distinct real roots of the equation f(x)=0f(x) = 0, find the value of SS.

29

Let y=f(x)y = f(x) be a differentiable function defined on (−∞,0)(-\infty, 0) satisfying the differential equation x2(dydx)2−2xydydx+2y2−x2=0x^2 \left(\frac{dy}{dx}\right)^2 - 2xy \frac{dy}{dx} + 2y^2 - x^2 = 0 If f(−1)=0f(-1) = 0 and f′(−1)>0f'(-1) > 0, then the value of f(−e−π/6)f(-e^{-\pi/6}) is:

30

Let ara_r be the term independent of tt in the binomial expansion of (t−1t)84−r(t+1t)r\left(t - \frac{1}{t}\right)^{84-r} \left(t + \frac{1}{t}\right)^r for r=0,1,2,…,84r = 0, 1, 2, \dots, 84. A polynomial f(x)f(x) is defined as f(x)=∑r=084(84r)arxrf(x) = \sum_{r=0}^{84} \binom{84}{r} a_r x^r. Which of the following correctly describes the parity of f(x)f(x) and the coefficient of x42x^{42} in f(x)f(x)?

31

Let f:R→Rf: \mathbb{R} \to \mathbb{R} be a continuous function satisfying the inequality 2x3−3x4≤f(x)≤2x3+3x42x^3 - 3x^4 \le f(x) \le 2x^3 + 3x^4 for all x∈(−1,1)x \in (-1, 1). A parametric curve is defined by x(t)=tan⁡t−tx(t) = \tan t - t and y(t)=f(t)y(t) = f(t) for t∈(−1,1)t \in (-1, 1). Evaluate the limit: lim⁡t→0y(t)x(t)\lim_{t \to 0} \frac{y(t)}{x(t)}

32

Let SS be the set of all real solutions to the equation cos⁡−1(16x5−20x3+5x)=2cos⁡−1x\cos^{-1}(16x^5 - 20x^3 + 5x) = 2\cos^{-1}x Find the value of ∑x∈Sx\sum_{x \in S} x.

33

Let f(x)=xex−1−1∣x−1∣+sin⁡(x−1)f(x) = \frac{x e^{x-1} - 1}{|x-1| + \sin(x-1)} for x≠1x \neq 1. If L1=lim⁡x→1+f(x)L_1 = \lim_{x \to 1^+} f(x) and L2=lim⁡x→1−f(x)L_2 = \lim_{x \to 1^-} f(x), then which of the following is correct?

34

Let t∈R∖{0}t \in \mathbb{R} \setminus \{0\} be a parameter. Define the determinants: D1(t)=∣t23t5110011∣andD2(t)=∣t23t−3110011∣D_1(t) = \begin{vmatrix} t^2 & 3t & 5 \\ 1 & 1 & 0 \\ 0 & 1 & 1 \end{vmatrix} \quad \text{and} \quad D_2(t) = \begin{vmatrix} t^2 & 3t & -3 \\ 1 & 1 & 0 \\ 0 & 1 & 1 \end{vmatrix} Consider the rational functions f1(x)=tx2−D1(t)x+1x+1f_1(x) = \frac{t x^2 - D_1(t) x + 1}{x + 1} and f2(x)=x2+D2(t)x+1tx−t2f_2(x) = \frac{x^2 + D_2(t) x + 1}{t x - t^2}. Let L1L_1 and L2L_2 be the oblique asymptotes of f1(x)f_1(x) and f2(x)f_2(x) respectively. Let SS be the set of all integers tt such that L1L_1 and L2L_2 intersect at a unique point P(xt,yt)P(x_t, y_t), and both xtx_t and yty_t are integers. Find the sum of all elements in SS.

35

Let y(x)y(x) be a continuous function on R\mathbb{R} satisfying the differential equation (x2+1)dydx+2xsgn(x)y=2x(x^2+1) \frac{dy}{dx} + 2x \text{sgn}(x) y = 2x for all x≠0x \neq 0, with the boundary condition y(−1)=−1y(-1) = -1. If A=lim⁡x→∞y(x)A = \lim_{x \to \infty} y(x), then the value of 1π∫0∞(A−y(x))dx\frac{1}{\pi} \int_0^\infty (A - y(x)) dx is equal to

36

Consider the function f(x)=2∣x−2∣−x2+4x−3f(x) = 2|x - 2| - x^2 + 4x - 3 defined on the interval [0,4][0, 4]. Let PP be the number of points in (0,4)(0, 4) where f(x)f(x) attains a local extremum. Let QQ be the number of points in (0,4)(0, 4) where f′(x)=0f'(x) = 0. Let RR be the number of intervals from the set S={[0,2],[1,3],[2,4]}S = \{[0, 2], [1, 3], [2, 4]\} on which Rolle's Theorem is applicable to f(x)f(x). Find the value of P2+Q2+R2P^2 + Q^2 + R^2.

37

Let A=[aij]A = [a_{ij}] be a square matrix of order 235235, where aij=∣i−j∣234cos⁡(i−j)+∣i−j∣235sin⁡(i−j)a_{ij} = |i-j|^{234} \cos(i-j) + |i-j|^{235} \sin(i-j) for all 1≤i,j≤2351 \le i, j \le 235. Let A=P+QA = P + Q, where PP is a symmetric matrix and QQ is a skew-symmetric matrix. What is the value of det⁡(Q2024+Q2025)+Tr(Q2025)\det(Q^{2024} + Q^{2025}) + \text{Tr}(Q^{2025})?

38

Let y=y(x)y = y(x) be a continuous solution to the differential equation dydx+3x∣x∣y=3x2\frac{dy}{dx} + 3x|x| y = 3x^2 for all x∈Rx \in \mathbb{R}. If y(1)=1+1ey(1) = 1 + \frac{1}{e}, then the value of y(−1)y(-1) is

39

Let f(x)=sgn(x2−5x+6)⋅∣x2−ax+b∣f(x) = \text{sgn}(x^2 - 5x + 6) \cdot |x^2 - ax + b|, where a,b∈Ra, b \in \mathbb{R}. If Rolle's Theorem is applicable to f(x)f(x) on the interval [1,4][1, 4], then the value of a+ba + b is:

40

Let f(x)=excos⁡xxf(x) = \frac{e^x \cos x}{x} for x≠0x \neq 0. Evaluate the integral I=∫−π/2π/2(sgn(x)f(x)+xsgn(x)f′(x)) dxI = \int_{-\pi/2}^{\pi/2} \left( \text{sgn}(x) f(x) + x \text{sgn}(x) f'(x) \right) \, dx where sgn(x)\text{sgn}(x) denotes the signum function.

41

Let y=f(x)y = f(x) be the real-valued differentiable solution to the differential equation sgn(y)dydx=3−2x\text{sgn}(y) \frac{dy}{dx} = 3 - 2x satisfying the initial condition f(1)=−2f(1) = -2. If D=(a,b)D = (a, b) is the maximum valid domain of f(x)f(x) and mm is the local minimum value of f(x)f(x) on DD, find the value of a+b−4ma + b - 4m.

42

Let f:[0,4]→Rf: [0, 4] \to \mathbb{R} be defined as f(x)=sgn(x)⋅(∣x2−4x+3∣+2)f(x) = \text{sgn}(x) \cdot \left( |x^2 - 4x + 3| + 2 \right) where sgn(x)\text{sgn}(x) denotes the signum function. If MM and mm are the absolute maximum and absolute minimum values of f(x)f(x) on the interval [0,4][0, 4] respectively, then the value of M+mM + m is:

43

Evaluate the following limit: lim⁡x→0[256−x2sin⁡2(1x)]x2+1\lim_{x \to 0} \frac{\left[ 256 - x^2 \sin^2\left(\frac{1}{x}\right) \right]}{x^2 + 1} where [⋅][ \cdot ] denotes the greatest integer function.

44

Let SS be the set of all ordered pairs (x,y)∈R2(x, y) \in \mathbb{R}^2 such that the complex number z=x+iyz = x + iy satisfies the following two equations: z2(3−4i)+zˉ2(3+4i)=0z^2 (3 - 4i) + \bar{z}^2 (3 + 4i) = 0 zzˉ−(3−i)z−(3+i)zˉ=0z \bar{z} - (3-i)z - (3+i)\bar{z} = 0 If the points in SS form the vertices of a triangle in the xyxy-plane, find the area of this triangle.

45

Let f(x)=x2−6x+10x2−6x+13+2−∣x−2∣−∣x−4∣f(x) = \frac{x^2 - 6x + 10}{x^2 - 6x + 13} + \sqrt{2 - |x-2| - |x-4|}. Find the range of f(x)f(x).

46

Let f:D→Rf: D \to \mathbb{R} be a function defined by f(x)=2sgn(x4−6x3+13x2−12x+4x3−4x2+5x−2)+sgn(x2−3x+2)f(x) = 2\text{sgn}\left( \frac{x^4 - 6x^3 + 13x^2 - 12x + 4}{x^3 - 4x^2 + 5x - 2} \right) + \text{sgn}(x^2 - 3x + 2) where DD is the maximal domain of definition of ff in R\mathbb{R}. Which of the following sets represents the range of f(x)f(x)?

47

Let B=[x121x−12−1x]B = \begin{bmatrix} x & 1 & 2 \\ 1 & x & -1 \\ 2 & -1 & x \end{bmatrix} and A=[aij]A = [a_{ij}] be a 3×33 \times 3 matrix where aija_{ij} is the minor of the element bijb_{ij} in BB. A mapping f:R3→R3f: \mathbb{R}^3 \to \mathbb{R}^3 is defined by f(V)=AVf(V) = AV, where VV is a 3×13 \times 1 column vector. If ff is not a one-to-one mapping, then the sum of the squares of all possible real values of xx is

48

Let f:R∖{2}→Rf: \mathbb{R} \setminus \{2\} \to \mathbb{R} be defined as f(x)=lim⁡h→01h∫xx+h(2t+t2sin⁡2(t−x)) dt+∣x−2∣x−2(x2−4x+c)f(x) = \lim_{h \to 0} \frac{1}{h} \int_{x}^{x+h} (2t + t^2 \sin^2(t-x)) \, dt + \frac{|x-2|}{x-2} (x^2 - 4x + c) Find the minimum integral value of cc for which f(x)f(x) is an injective (one-to-one) function.

49

Let f(x)=sin⁡−1(2x1−x2)−2sin⁡−1x+sec⁡−1(2x)f(x) = \sqrt{ \sin^{-1}(2x\sqrt{1-x^2}) - 2\sin^{-1}x } + \sec^{-1}(2x). Find the domain of f(x)f(x).

50

Let SS be the domain of the real-valued function f(x)=sin⁡−1(x3−12(x−1)−x22)+cos⁡−1(x2−xx)f(x) = \sin^{-1}\left( \frac{x^3 - 1}{2(x - 1)} - \frac{x^2}{2} \right) + \cos^{-1}\left( \frac{x^2 - x}{x} \right) Find the number of integers in the set SS.

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