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Two functions f and g are defined on the set R of real numbe...

Two functions f and g are defined on the set R of real numbers by f:x2x1 and g:xx2+1. Find the value of f1g(3).

A.

12

B.

11

C.

112

D.

92

Correct answer is C

f(x)=2x1;g(x)=x2+1

f(x)=2x1

f(y)=2y1

x=2y12y=x+1

y=x+12

g(3)=32+1=10

f1(10)=10+12=112