Question

f x is real, solve for x : (i) 1 = 1

Answer 1

Answer:

Correct option is

Cx

f(x)=

x−1

x+1

f(f(x))=

f(x)−1

f(x)+1

=

(

x−1

x+1

)

−1

(

x−1

x+1

)

+1

=

x−1

x+1−x+1

x−1

x+1+x−1

=

x−1

2

x−1

2x

=

2

2x

=

x

Now,

f(f(x))=

x