*According to the CBSE Syllabus 2023-24, this chapter has been renumbered as Chapter 6.
NCERT Solutions for Class 11 Maths Chapter 7 Exercise 7.2 have been carefully compiled and developed as per the latest CBSE Syllabus and its guidelines. These NCERT Solutions contain a detailed step-by-step explanation of all the problems that are present in the prescribed textbook. Exercise 7.2 of NCERT Solutions for Class 11 Maths Chapter 7- Permutations and Combinations is based on the following topics:
- Permutations
- Permutations when all the objects are distinct
- Factorial notation
The NCERT Solutions for Class 11 Maths enhance topics with frequent, focused, engaging challenges and activities that strengthen Math concepts. Each question of the exercise has been carefully solved for the students to understand, keeping the board examination in mind.
NCERT Solutions for Class 11 Maths Chapter 7 – Permutations and Combinations Exercise 7.2
Access NCERT Solutions for Class 11 Maths Chapter 7 – Exercise 7.2
1. Evaluate
(i) 8!
(ii) 4! – 3!
Solution:
(i)Â Consider 8!
We know that 8! = 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1
= 40320
(ii)Â Consider 4!-3!
4!-3! = (4 × 3!) – 3!
Above equation can be written as
= 3! (4-1)
= 3 × 2 × 1 × 3
= 18
2. Is 3! + 4! = 7!?
Solution:
Consider LHS 3! + 4!
Computing left hand side, we get
3! + 4! = (3 × 2 × 1) + (4 × 3 × 2 × 1)
= 6 + 24
= 30
Again considering RHS and computing, we get
7! = 7 × 6 × 5 × 4 × 3 × 2 × 1 = 5040
Therefore LHS ≠RHS
Therefore 3! + 4! ≠7!
3. ComputeÂ
Solution:
4. If 
find x.
Solution:
5. Evaluate
 
,
When
(i) n = 6, r = 2
(ii) n = 9, r = 5
Solution:
Access Other Exercise Solutions of Class 11 Maths Chapter 7 – Permutations and Combinations
Exercise 7.1 Solutions 6 Questions
Exercise 7.3 Solutions 11 Questions
Exercise 7.4 Solutions 9 Questions
Miscellaneous Exercise On Chapter 7 Solutions 11 Questions
Also explore – NCERT Class 11 Solutions
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