NCERT Solutions
Class 11 - Mathematics - Chapter 6: PERMUTATIONS AND COMBINATIONS
EXERCISE 6.2

Question. 1

Evaluate:

(i) \(8!\)

(ii) \(4! - 3!\)

Answer:

(i) 40320

(ii) 18

Question. 2

Is \(3! + 4! = 7!\)?

Answer:

30, No

Question. 3

Compute \(\dfrac{8!}{6! \times 2!}\)

Answer:

28

Question. 4

If \(\dfrac{1}{6!} + \dfrac{1}{7!} = \dfrac{x}{8!}\), find \(x\)

Answer:

64

Question. 5

Evaluate \(\dfrac{n!}{(n-r)!}\) for:

(i) \(n = 6, r = 2\)

(ii) \(n = 9, r = 5\)

Answer:

(i) 30

(ii) 15120

NCERT Solutions Class 11 – Mathematics – Chapter 6: PERMUTATIONS AND COMBINATIONS – EXERCISE 6.2 | Detailed Answers