IP-Header
March 12, 2024
Theory-of-Computation
March 12, 2024
IP-Header
March 12, 2024
Theory-of-Computation
March 12, 2024

UGC NET CS 2017 Jan -paper-2

Question 3
The functions mapping R into R are defined as : f(x) = x​ 3​ – 4x, g(x) = 1/(x​ 2​ + 1) and h(x) =
x​ 4​ . Then find the value of the following composite functions : hog(x) and hogof(x)
A
(x​ 2​ + 1)4 and [(x​ 3​ – 4x)​ 2​ + 1]​ 4
B
(x​ 2​ + 1)4 and [(x​ 3​ – 4x)​ 2​ + 1]​ -4
C
(x​ 2​ + 1)-4 and [(x​ 3​ – 4x)​ 2​ + 1]​ 4
D
(x​ 2​ + 1)-4 and [(x​ 3​ – 4x)​ 2​ + 1]​ -4
Question 3 Explanation: 
Step-1: Given data,
f(x) = x​ 3​ – 4x, g(x) = 1/(x​ 2​ + 1) and h(x) = x​ 4
hog(x)=h(1/(x​ 2​ + 1))
=h(1/(x​ 2​ )+1)​ 4
= 1/(x​ 2​ +1)​ 4
= (x​ 2​ +1)​ -4
hogof(x)= hog(x​ 3​ -4x)
= h(1/(x​ 3​ -4x)​ 2​ +1)
= h(1/(x​ 3​ -4x)​ 2​ +1)​ 4
= h((x​ 3​ -4x)​ 2​ +1)​ -4
So, option D id is correct answer.
Correct Answer: D
Question 3 Explanation: 
Step-1: Given data,
f(x) = x​ 3​ – 4x, g(x) = 1/(x​ 2​ + 1) and h(x) = x​ 4
hog(x)=h(1/(x​ 2​ + 1))
=h(1/(x​ 2​ )+1)​ 4
= 1/(x​ 2​ +1)​ 4
= (x​ 2​ +1)​ -4
hogof(x)= hog(x​ 3​ -4x)
= h(1/(x​ 3​ -4x)​ 2​ +1)
= h(1/(x​ 3​ -4x)​ 2​ +1)​ 4
= h((x​ 3​ -4x)​ 2​ +1)​ -4
So, option D id is correct answer.

Leave a Reply

Your email address will not be published. Required fields are marked *