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If g(x)=x+1x2,x2, find \(g^{-1}(...

If g(x)=x+1x2,x2, find g1(2).

A.

3

B.

2

C.

34

D.

-3

Correct answer is D

g(x)=x+1x+2,x2

Let y = x, then g(y)=y+1y+2

Let x = g(y), so that x=y+1y+2

x(y+2)=y+1

xy+2x=y+1xyy=12x

y(x1)=12xy=12xx1

y=g1(x)=12xx1

g1(2)=12(2)21=3