RS Aggarwal - Mathematics

Book: RS Aggarwal - Mathematics

Chapter: 3. Functions

Subject: Maths - Class 11th

Q. No. 8 of Exercise 3F

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8

Let A = {6, 10, 11, 15, 12} and let f : A → N : f(n) is the highest prime factor of n. Find range (f).

Given, A = {6, 10, 11, 15, 12}


f : A → N : f(n) is the highest prime factor of n


(1) When n = 6, the highest prime factor of 6 is 3.


Hence, f(6) = 3.


(2) When n = 10, the highest prime factor of 10 is 5.


Hence, f(10) = 5.


(3) When n = 11, the highest prime factor of 11 is 11 as 11 itself is a prime number.Hence, f(11) = 11.


(4) When n = 15, the highest prime factor of 15 is 5.


Hence, f(15) = 5.


(5) When n = 12, the highest prime factor of 12 is 3.


Hence, f(12) = 3.


Hence range of f is { 3,5,11}.


Chapter Exercises

Exercise 3B
Exercise 3C
Exercise 3D
Exercise 3E
Exercise 3F
Exercise 3A

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