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A function f is defined by \(f :x→\frac{x + 2}{x - ...

A function f is defined by f:xx+2x3,x3.Find the inverse of f .

A.

x+3x2,x2

B.

x3x+2,x2

C.

3x2x+1,x1

D.

3x+2x1,x1

Correct answer is D

f:xx+2x3,x3,f=?

Let f:x=y

y=x+2x3

=x+2=y(x3)

=xxy=3y2

=x(1y)=3y2

=x=3y21y=(3y+2)(y1)

=x=3y+2y1

∴f ^{-1} : x=\frac{3x + 2}{x - 1},x ≠ 1