(7).Given f(x) =
[tex] \frac{1}{x ^{2} - 1} [/tex]
and g(x)=
[tex] \frac{x}{x + 2} [/tex]
where x & R.

Find the ;
(i). inverse of g(x) (ii). Expression
[tex] g{x} ^{ - 1} f{x}[/tex]

iii). Largest domain of f(x) and g(x) respectively.​

Respuesta :

Answer:

The inverse of g(x) is [tex]g^{-1}(x)=\frac{2x}{1-x}[/tex]

The domain of g(x) is (-∞,-2)U(-2,∞)

The domain of f(x) is (-∞,-1)U(-1,1)U(1,∞)

Step-by-step explanation:

Find the inverse of g(x).

[tex]y=\frac{x}{x+2}[/tex]

Solve for x

[tex]x=y(x+2)[/tex]

[tex]x=xy+2y[/tex]

[tex]x(1-y)=2y[/tex]

[tex]x=\frac{2y}{1-y}[/tex]

[tex]g^{-1}(x)=\frac{2x}{1-x}[/tex]

Find the domain of g(x)

[tex]g(x)=\frac{x}{x+2}[/tex]

Numerator and denominator have domain

(-∞,∞).

However, g(x) is undefined if the denominator is 0.  Hence, x=-2 must be taken out of the domain. So, the domain of g(x) is

(-∞,-2)U(-2,∞).

Find the domain of f(x)

[tex]f(x)=\frac{1}{x^{2} -1}[/tex]

The numerator and denominator have the domain

(-∞,∞)

However, f(x) is undefined if the denominator is 0.  This rules out +1 and -1. So, the domain of f(x) is

(-∞,-1)U(-1,1)U(1,∞)

I am not sure what you mean for (ii).