UG Mathematics Booster Test 1 - Introduction and Basic Concepts
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QUESTION 1 OF 20
The concept of a mathematical relation is generalized from which of the following real-world applications?
QUESTION 2 OF 20
Let A = {1, 2}. A subset of A × A is chosen at random to form a relation. What is the probability that the chosen relation is the universal relation?
QUESTION 3 OF 20
Roster form lists elements explicitly. Which of the sets below correctly represent the relation R = {(x,y) : x+y=5, x,y ∈ N}?
I. {(1,4), (2,3)}
II. {(3,2), (4,1)}
III. {(0,5)}
QUESTION 4 OF 20
Which is an incorrect characteristic of the set-builder form of a relation?
QUESTION 5 OF 20
Match the given relations to their corresponding domains (assuming natural numbers):
| List I | List II |
|---|---|
| 1. {(1,2), (3,4)} | a. {1, 2} |
| 2. {(x,y) : y = x, x < 3} | b. {2} |
| 3. {(2,1), (2,3)} | c. {1, 3} |
| 4. y = x², for x ∈ {4} | d. {4} |
QUESTION 6 OF 20
A chemical mixture problem defines a relation between time (x) and concentration percentage (y):
R = {(1, 10), (2, 20), (3, 30)}. If the range values represent proportions out of 100, what is the average of the range elements?
QUESTION 7 OF 20
Assertion (A): The relation R = {(1,2), (1,3)} is a valid function.
Reason (R): In a function, an element in the domain cannot map to multiple distinct elements in the codomain.
QUESTION 8 OF 20
Given f(x) = x² for x = 1, 2, 3, 4, 5. The sequential output values are 1, 4, 9, 16, 25. Calculate the first three 3-period moving averages. What is the lowest moving average among them?
QUESTION 9 OF 20
What geometric boundary is formed by the graph of the relation |x| + |y| = 1?
QUESTION 10 OF 20
Arrange the analytical steps to visually verify if a mapping diagram from set X to set Y represents a function:
1. Check if any domain element has no arrow originating from it.
2. Identify the domain set X.
3. Conclude it is a function if each element in X has exactly one arrow.
4. Check if any domain element has more than one arrow.
QUESTION 11 OF 20
QUESTION 12 OF 20
QUESTION 13 OF 20
An ordered pair (x, y) can represent a 2D vector. If the relation maps any vector v to a new vector 2v, what is the resulting image of the vector represented by (3, -1)?
QUESTION 14 OF 20
If the relation notation aRb mathematically signifies that b = 4a³, what is the area under the curve formed by this relation evaluated from a = 0 to a = 1?
QUESTION 15 OF 20
A universal relation on the set of real numbers restricted from 0 to 2 is the Cartesian product ×. What is the area of this region in the coordinate plane?
QUESTION 16 OF 20
Match the function f: R → R with its conceptual type:
| List I | List II |
|---|---|
| 1. f(x) = x | a. One-one and onto |
| 2. f(x) = x² | b. Many-one, not onto |
| 3. f(x) = 3 | c. Many-one (Constant) |
| 4. f(x) = e^x | d. One-one, not onto |
QUESTION 17 OF 20
Assertion (A): In general function compositions, fog is not equal to gof.
Reason (R): Composition of functions is always a commutative operation.
QUESTION 18 OF 20
Which of the following conditions must hold for a function f to have a valid inverse?
I. f must be injective.
II. f must be a polynomial.
III. f must be surjective.
QUESTION 19 OF 20
Arrange the analytical process of formalizing a real-life relation into mathematical notation:
1. Define the sets involved (e.g., set of people A).
2. Represent the set as R subset of A × A.
3. Identify the real-life link (e.g., "is a friend of").
4. Write out the specific ordered pairs (x, y) fulfilling the link.
QUESTION 20 OF 20
Which is an incorrect statement about abstract equivalence relations?
Test Complete!
Answer Review
1 The concept of a mathematical relation is generalized from which of the following real-world applications?
Relation idea comes from everyday language Mathematical relations express connections NCERT introduces relation concept similarly
The mathematical idea of relation originates from recognizable connections between objects in ordinary English language usage. NCERT explains that mathematical relations abstract real-life associations into ordered pairs and subsets of Cartesian products. Hence Option B is correct. Physics, geometry, and chemistry are unrelated to the conceptual origin of relations.
- Option A → Energy transfer belongs to physics concepts, not set-theoretic relation origin.
- Option C → Geometric axioms define geometry foundations, not relations.
- Option D → Atomic bonding is a chemistry concept unrelated to mathematical relation definitions.
Used: Contextual/Tonal Matching
Application:
- Match the conceptual origin described in NCERT with real-world language usage.
Final Logic:
- Relations mathematically model recognizable connections between objects.
"Relation = Connection"
2 Let A = {1, 2}. A subset of A × A is chosen at random to form a relation. What is the probability that the chosen relation is the universal relation?
A × A has 4 elements Total relations = 2⁴ = 16 Only one universal relation exists
Since A = {1,2}, the Cartesian product A × A contains 4 ordered pairs. Total possible relations are subsets of A × A, equal to 2⁴ = 16. The universal relation contains all ordered pairs and is unique. Therefore probability = 1/16. Hence Option C is correct.
- Option A → Assumes incorrect total number of relations.
- Option B → Uses 8 total relations instead of 16.
- Option D → Universal relation is only one among all possible subsets.
Used: Substitution
Application:
- Substitute number of elements into relation-count formula 2^(n²).
Final Logic:
- Only one universal relation exists among 16 possible relations.
"Universal = Full set only once"
3 Roster form lists elements explicitly. Which of the sets below correctly represent the relation R = {(x,y) : x+y=5, x,y ∈ N}?
I. {(1,4), (2,3)}
II. {(3,2), (4,1)}
III. {(0,5)}
Natural numbers exclude 0 here Pairs must satisfy x+y=5 Both I and II satisfy condition
For x,y ∈ N and x+y=5, valid ordered pairs include (1,4), (2,3), (3,2), and (4,1). Thus Statements I and II are correct. Statement III contains 0, which is not taken as a natural number in standard NCERT convention. Hence Option D is correct.
- Option A → Ignores valid ordered pairs in Statement II.
- Option B → Ignores valid ordered pairs in Statement I.
- Option C → Includes Statement III, which violates natural number condition.
Used: Elimination
Application:
- Check each ordered pair against the condition x+y=5 and natural number restriction.
Final Logic:
- Only Statements I and II fully satisfy the relation.
"Sum 5, no zero"
4 Which is an incorrect characteristic of the set-builder form of a relation?
Set-builder uses rules, not full listing Symbols mean "such that" Useful for infinite relations
Set-builder form describes a relation using a condition or rule instead of explicitly listing all ordered pairs. Hence Option A is incorrect. Options B and C correctly describe notation and purpose. Option D is also correct because infinite sets are conveniently represented using conditions rather than exhaustive listing.
- Option B → Correct because set-builder form specifies defining conditions.
- Option C → Correct since ":" or "|" means "such that."
- Option D → Infinite sets are efficiently represented through rules.
Used: Extreme Word Filter
Application:
- The word "always" signals an overly broad and incorrect statement.
Final Logic:
- Explicit listing belongs to roster form, not set-builder form.
"Builder uses rules, not lists"
5 Match the given relations to their corresponding domains (assuming natural numbers):
| List I | List II |
|---|---|
| 1. {(1,2), (3,4)} | a. {1, 2} |
| 2. {(x,y) : y = x, x < 3} | b. {2} |
| 3. {(2,1), (2,3)} | c. {1, 3} |
| 4. y = x², for x ∈ {4} | d. {4} |
Domain contains first elements Extract x-values from relations Match domains carefully
For Relation 1, domain = {1,3} → c. For Relation 2, x < 3 in natural numbers gives {1,2} → a. For Relation 3, only first element is 2 → b. For Relation 4, x belongs to {4} → d. Thus Option B is correct.
- Option A → Incorrectly assigns domain of Relation 1.
- Option C → Misidentifies domain of Relation 2.
- Option D → Completely mismatches domains for Relations 1 and 4.
Used: Option Grouping
Application:
- Identify first coordinates systematically and match them with domain sets.
Final Logic:
- Domain always consists of all first components.
"Domain = Left side values"
6 A chemical mixture problem defines a relation between time (x) and concentration percentage (y):
R = {(1, 10), (2, 20), (3, 30)}. If the range values represent proportions out of 100, what is the average of the range elements?
Range values are 10, 20, 30 Average = sum ÷ number Result equals 20
The range of the relation consists of second coordinates: 10, 20, and 30. Their average is: (10+20+30)/3 = 60/3 = 20. Hence Option C is correct. Other options either represent totals or individual values instead of the arithmetic mean.
- Option A → Represents smallest range value only.
- Option B → Represents largest range value only.
- Option D → Equals total sum, not average.
Used: Substitution
Application:
- Extract range values and apply average formula directly.
Final Logic:
- Average = (10+20+30)/3 = 20.
"Add outputs, divide count"
7 Assertion (A): The relation R = {(1,2), (1,3)} is a valid function.
Reason (R): In a function, an element in the domain cannot map to multiple distinct elements in the codomain.
Input 1 has two outputs Functions allow unique image only Reason correctly states function rule
The relation {(1,2),(1,3)} is not a function because the element 1 maps to two different outputs. Therefore Assertion is false. The Reason is true because a function requires each domain element to have exactly one image in the codomain. Hence Option D is correct.
- Option A → Reason is mathematically correct.
- Option B → Assertion is false since uniqueness condition fails.
- Option C → Assertion itself is incorrect, so explanation cannot hold.
Used: Elimination
Application:
- Check whether any input corresponds to more than one output.
Final Logic:
- One input with two outputs violates function definition.
"One input → one output"
8 Given f(x) = x² for x = 1, 2, 3, 4, 5. The sequential output values are 1, 4, 9, 16, 25. Calculate the first three 3-period moving averages. What is the lowest moving average among them?
Moving averages use consecutive triples Averages are 14/3, 29/3, and 50/3 Lowest is 14/3
The outputs are 1, 4, 9, 16, 25. First 3-period average = (1+4+9)/3 = 14/3. Second = (4+9+16)/3 = 29/3. Third = (9+16+25)/3 = 50/3. The lowest moving average is 14/3. Hence Option A is correct.
- Option B → Represents the second moving average.
- Option C → Incorrect arithmetic calculation.
- Option D → Represents the third moving average.
Used: Substitution
Application:
- Compute consecutive averages carefully using grouped outputs.
Final Logic:
- Lowest among computed moving averages is 14/3.
"First window gives smallest average"
9 What geometric boundary is formed by the graph of the relation |x| + |y| = 1?
Absolute value creates straight segments Boundary joins four vertices Resulting figure is a square
The equation |x| + |y| = 1 forms four linear boundaries in different quadrants. The graph connects points (1,0), (0,1), (-1,0), and (0,-1), producing a square rotated by 45°. Therefore Option B is correct. It is neither circular nor parabolic in shape.
- Option A → Circle follows x²+y²=r², not absolute value equation.
- Option C → Figure has four vertices, not three.
- Option D → Parabola arises from quadratic equations, not modulus sums.
Used: Contextual/Tonal Matching
Application:
- Interpret modulus equation geometrically by examining quadrant-wise linear behavior.
Final Logic:
- Four straight boundary segments form a square.
"|x|+|y| gives diamond square"
10 Arrange the analytical steps to visually verify if a mapping diagram from set X to set Y represents a function:
1. Check if any domain element has no arrow originating from it.
2. Identify the domain set X.
3. Conclude it is a function if each element in X has exactly one arrow.
4. Check if any domain element has more than one arrow.
Start with identifying domain Verify arrow conditions carefully Conclude function at end
To verify a function visually, first identify the domain set X. Next check whether any domain element lacks an arrow. Then verify that no domain element has multiple arrows. Finally conclude whether each element has exactly one image. Thus the correct order is 2 → 1 → 4 → 3, making Option C correct.
- Option A → Conclusion cannot be reached before checking multiple arrows.
- Option B → Domain identification should come first logically.
- Option D → Conclusion must always appear after verification steps.
Used: Contextual/Tonal Matching
Application:
- Arrange steps according to logical mathematical verification flow.
Final Logic:
- Identify → verify arrows → conclude function status.
"Check domain, then arrows"
11
Sibling relation works mutually If a is sibling of b, reverse also true Relation is symmetric in nature
The sibling relation is symmetric because if a is a sibling of b, then b is also a sibling of a. Hence Option D is correct. It is not reflexive since a person is not their own sibling. It is also not asymmetric because symmetry clearly exists.
- Option A → Sibling relation is not reflexive because no person is sibling of themselves.
- Option B → Sibling relation alone does not establish transitivity strictly in relation theory.
- Option C → Asymmetric relations cannot be symmetric simultaneously.
Used: Contextual/Tonal Matching
Application:
- Interpret family relation properties using the passage definitions directly.
Final Logic:
- Sibling relation satisfies mutual connection, hence symmetric.
"Sibling works both ways"
12
x ≤ x always true Order relation preserves transitivity Reverse condition need not hold
The relation x ≤ y is reflexive because every number satisfies x ≤ x. It is transitive because x ≤ y and y ≤ z imply x ≤ z. However, it is not symmetric since x ≤ y does not imply y ≤ x unless x = y. Hence Option A is correct.
- Option B → Relation is not symmetric in general.
- Option C → Symmetry fails whenever x < y.
- Option D → Symmetry is not satisfied for order relations.
Used: Elimination
Application:
- Check each property individually using standard inequality examples.
Final Logic:
- ≤ is reflexive and transitive but not symmetric.
"Less-than keeps order forward only"
13 An ordered pair (x, y) can represent a 2D vector. If the relation maps any vector v to a new vector 2v, what is the resulting image of the vector represented by (3, -1)?
Multiply each component by 2 Vector scaling doubles coordinates Result becomes (6, -2)
The transformation v → 2v doubles every component of the vector. For vector (3,−1), multiplying each coordinate by 2 gives (6,−2). Therefore Option B is correct. Other options either partially scale coordinates or incorrectly change signs.
- Option A → Only y-coordinate is doubled incorrectly.
- Option C → Represents halving instead of doubling.
- Option D → Changes sign unnecessarily while scaling.
Used: Substitution
Application:
- Apply scalar multiplication directly to vector coordinates.
Final Logic:
- 2(3,−1) = (6,−2).
"Scalar multiplies every coordinate"
14 If the relation notation aRb mathematically signifies that b = 4a³, what is the area under the curve formed by this relation evaluated from a = 0 to a = 1?
Integrate 4a³ from 0 to 1 Antiderivative becomes a⁴ Final value equals 1
The required area is: \(\int_{0}^{1}\,4a^{3} da\) Integrating gives a⁴ evaluated from 0 to 1: 1⁴ − 0⁴ = 1. Hence Option C is correct. Other options arise from incorrect integration rules or coefficient handling.
- Option A → Incorrect evaluation after integration.
- Option B → Results from arithmetic error.
- Option D → Equals coefficient only, not integral value.
Used: Substitution
Application:
- Replace b with 4a³ and apply definite integration directly.
Final Logic:
- ∫₀¹4a³da = [a⁴]₀¹ = 1.
"Power +1 cancels coefficient"
15 A universal relation on the set of real numbers restricted from 0 to 2 is the Cartesian product ×. What is the area of this region in the coordinate plane?
Cartesian product forms square region Side length equals 2 Area = 2 × 2 = 4
The universal relation on [0,2] consists of all ordered pairs (x,y) where both coordinates lie between 0 and 2. This forms a square region in the coordinate plane with side length 2. Therefore area = 2 × 2 = 4. Hence Option D is correct.
- Option A → Represents only one dimension length.
- Option B → Incorrect multiplication beyond square area.
- Option C → Does not correspond to Cartesian square geometry.
Used: Dimensional/Unit Analysis
Application:
- Interpret Cartesian product geometrically as a rectangular region.
Final Logic:
- [0,2] × [0,2] forms square of area 4.
"Cartesian square → side²"
16 Match the function f: R → R with its conceptual type:
| List I | List II |
|---|---|
| 1. f(x) = x | a. One-one and onto |
| 2. f(x) = x² | b. Many-one, not onto |
| 3. f(x) = 3 | c. Many-one (Constant) |
| 4. f(x) = e^x | d. One-one, not onto |
Identity function is bijective x² is many-one and not onto e^x is one-one but not onto R
f(x)=x is both one-one and onto → a. f(x)=x² maps x and −x together and misses negatives → b. f(x)=3 is constant and many-one → c. f(x)=e^x is injective but its range excludes negative reals → d. Thus Option A is correct.
- Option B → Incorrectly classifies exponential function as onto R.
- Option C → x² is not one-one and onto over R.
- Option D → Constant function is not onto over real numbers.
Used: Option Grouping
Application:
- Compare injective and surjective properties of standard functions.
Final Logic:
- Each function matches its textbook mapping behavior.
"Identity bijective, square many-one"
17 Assertion (A): In general function compositions, fog is not equal to gof.
Reason (R): Composition of functions is always a commutative operation.
Function composition order matters Composition is generally non-commutative Reason contradicts actual property
In general, fog ≠ gof because the order of applying functions affects outputs. Hence Assertion is true. The Reason is false because function composition is not commutative in general. Therefore Option B is correct according to standard properties of composite functions.
- Option A → Assertion is mathematically correct.
- Option C → Reason itself is false and cannot explain Assertion.
- Option D → Composition usually depends on order, so Assertion is true.
Used: Extreme Word Filter
Application:
- The word "always" signals incorrect universal generalization.
Final Logic:
- Composition is generally non-commutative.
"Order matters in composition"
18 Which of the following conditions must hold for a function f to have a valid inverse?
I. f must be injective.
II. f must be a polynomial.
III. f must be surjective.
Inverse requires bijection Bijection means injective and surjective Polynomial condition unnecessary
A function has a valid inverse only if it is bijective. Bijective means both injective (one-one) and surjective (onto). Thus Statements I and III are necessary. Statement II is not required because invertible functions need not be polynomials. Therefore Option C is correct.
- Option A → Injectivity alone does not guarantee inverse over codomain.
- Option B → Polynomial form is unrelated to invertibility requirement.
- Option D → Surjectivity alone cannot ensure uniqueness of inverse.
Used: Elimination
Application:
- Use the theorem: invertible ⇔ bijective.
Final Logic:
- Inverse exists only for one-one and onto functions.
"Inverse needs bijection"
19 Arrange the analytical process of formalizing a real-life relation into mathematical notation:
1. Define the sets involved (e.g., set of people A).
2. Represent the set as R subset of A × A.
3. Identify the real-life link (e.g., "is a friend of").
4. Write out the specific ordered pairs (x, y) fulfilling the link.
Begin with real-life connection Define involved sets next Then form ordered pairs and relation
To formalize a relation, first identify the real-life link. Then define the relevant sets involved. Next list ordered pairs satisfying the relation. Finally express the relation formally as a subset of Cartesian product. Hence the correct order is 3 → 1 → 4 → 2, making Option D correct.
- Option A → Formal notation appears before identifying the relation meaning.
- Option B → Sets should be defined before writing ordered pairs.
- Option C → Cartesian representation cannot precede relation formation steps.
Used: Contextual/Tonal Matching
Application:
- Arrange steps according to natural mathematical modeling process.
Final Logic:
- Identify relation → define set → form pairs → formalize subset.
"Link → Set → Pairs → Relation"
20 Which is an incorrect statement about abstract equivalence relations?
Equivalence classes are disjoint Their union forms original set Related elements belong together
Equivalence relations partition a set into mutually disjoint equivalence classes. Therefore Option A is incorrect because equivalence classes never overlap. Options B, C, and D correctly describe partition properties and relation behavior within the same equivalence class.
- Option B → Correct property of equivalence class partitioning.
- Option C → Entire set is covered by equivalence classes together.
- Option D → Members of same class satisfy the equivalence relation.
Used: Odd One Out
Application:
- Identify the statement contradicting partition properties of equivalence relations.
Final Logic:
- Equivalence classes are always disjoint, never overlapping.
"Equivalence classes never overlap"
