CATKing Forum
Home FAQs
Add New Thread
Privacy Policy Articles
CAT Question Paper | CAT Verbal Ability Slot
CATKing Student
Question :

For any non-zero real number x, let f(x)+2f(1/x)=3x. Then, the sum of all possible values of x for which f(x)=3, is

Started 4 hours ago by Admin in

0 replies 4 views
Option B is the correct answer.

Explanatory Answer

 

f(x)+2f(1x)=3x

Put x=1/x,

f(1x)+2f(x)=3x

Solving (1) & (2),
(1) ⇒

(1)⇒2×(2)⇒f(x)+2f(1x)=3x2f(1x)+4f(x)=6x

Subtracting, we get

3f(x)=6x−3x

So,

f(x)=2x−x

Now,

f(x)=3 implies, 2x−x=3x2+3x−2=0

Sum of the roots =−b/a
Answer =−3

 

The question is "For any non-zero real number x, let f(x)+2f(1x)=3x. Then, the sum of all possible values of x for which f(x)=3, is"

Hence, the answer is '-3'
  • No one is replied to this question yet. Be first to reply!