Application of Derivatives 2 Question 7

7. If the function g:(,)π2,π2 is given by g(u)=2tan1(eu)π2. Then, g is

(2008, 3M)

(a) even and is strictly increasing in (0,)

(b) odd and is strictly decreasing in (,)

(c) odd and is strictly increasing in (,)

(d) neither even nor odd but is strictly increasing in (,)

Show Answer

Solution:

  1. Given, g(u)=2tan1(eu)π2 for u(,)

g(u)=2tan1(eu)π2=2(cot1(eu))π2=2π2tan1(eu)π2=π/22tan1(eu)=g(u)g(u)=g(u)g(u) is an odd function. 

We have, g(u)=2tan1(eu)π/2

g(u)=2eu1+e2ug(u)>0,xR

[eu>0]

So, g(u) is increasing for all xR.



जेईई के लिए मॉक टेस्ट

एनसीईआरटी अध्याय वीडियो समाधान

दोहरा फलक