Sets and Relations for JEE Main
Sets and Relations builds the language used throughout Mathematics. Questions usually focus on set operations, counting elements, Cartesian products, relation properties and identifying whether a relation is reflexive, symmetric or transitive.
For better accuracy, first write the universal set and definitions clearly. In relation questions, test every required condition one by one instead of deciding from a few examples.
Important Topics to Revise
Revise these connected concepts before solving JEE Main Sets and Relations questions.
Types of Sets
Empty, finite, infinite, singleton, equal, equivalent and universal sets.
Set Operations
Union, intersection, difference, complement and De Morgan's laws.
Venn Diagrams
Use inclusion-exclusion to count elements in two or three sets.
Cartesian Product
Ordered pairs and the number of elements in \(A \times B\).
Relations
Domain, range, inverse relation and subsets of \(A \times B\).
Relation Properties
Reflexive, symmetric, transitive and equivalence relations.
Sets and Relations Formula Revision
JEE Main Sets and Relations Questions with Answers
Try the questions before opening the answer explanations.
If \(A=\{1,2,3,4\}\) and \(B=\{3,4,5,6\}\), then \(A \cap B\) is:
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Answer: B. The intersection contains only elements common to both sets. The common elements are 3 and 4.
In a group of 50 students, 28 study Mathematics, 22 study Physics and 10 study both. How many study at least one of the two subjects?
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Answer: C. \(n(M \cup P)=28+22-10=40\). Students studying both subjects are counted once in the union.
If \(A=\{a,b,c\}\) and \(B=\{1,2\}\), the number of elements in \(A \times B\) is:
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Answer: C. \(n(A \times B)=n(A)n(B)=3 \times 2=6\).
If \(A\) has 2 elements and \(B\) has 3 elements, the number of relations from \(A\) to \(B\) is:
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Answer: D. A relation from \(A\) to \(B\) is any subset of \(A \times B\). Since \(n(A\times B)=2\times3=6\), the number of subsets is \(2^6=64\).
Let \(U=\{1,2,3,4,5,6,7,8\}\) and \(A=\{2,4,6,8\}\). Then \(A'\) is:
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Answer: B. The complement of \(A\) contains all elements of the universal set that are not in \(A\).
On the set \(A=\{1,2,3\}\), define \(R=\{(1,1),(2,2),(3,3),(1,2),(2,1)\}\). The relation \(R\) is:
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Answer: D. All pairs \((a,a)\) are present, so it is reflexive. The pairs \((1,2)\) and \((2,1)\) occur together, so it is symmetric. It is also transitive; therefore it is an equivalence relation.
The complement of \(A \cup B\) is equal to:
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Answer: B. By De Morgan's law, \((A \cup B)'=A' \cap B'\).
The number of proper subsets of a set containing 5 elements is:
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Answer: C. A 5-element set has \(2^5=32\) subsets. Excluding the set itself gives 31 proper subsets.
Continue Your JEE Main Mathematics Practice
After revising Sets and Relations, move to Functions, Trigonometric Functions and other connected chapters. Review wrong answers before starting a new question set.
Explore Available Free TestsHow to Prepare Sets and Relations for JEE Main
- Learn the notation and definitions before memorising formulas.
- Draw Venn diagrams for word problems involving two or three groups.
- Write ordered pairs explicitly when working with Cartesian products and relations.
- Check reflexive, symmetric and transitive conditions separately.
- Practise counting questions involving subsets and relations until the formulas become familiar.
Common mistakes to avoid
- Confusing \(A-B\) with \(B-A\).
- Counting common elements twice in a union.
- Treating \((a,b)\) and \((b,a)\) as the same ordered pair.
- Calling a relation an equivalence relation without checking transitivity.
- Forgetting to define the universal set when taking complements.
JEE Main Sets and Relations FAQs
Is Sets and Relations important for JEE Main Mathematics?
Yes. It is a foundation chapter and its notation, functions and relation concepts connect with several later Mathematics topics.
What are the most important topics in Sets and Relations?
Set operations, Venn diagrams, Cartesian products, number of relations, and reflexive, symmetric and transitive relations are important revision areas.
How many relations are possible from A to B?
If \(A\) has \(m\) elements and \(B\) has \(n\) elements, there are \(2^{mn}\) possible relations from \(A\) to \(B\).
Are these official JEE Main previous-year questions?
No. These are original JEE Main-style practice questions created for revision. Consult official sources for exact previous-year papers.