Find the inverse function of [tex]g(x)=\frac{\sqrt{x}+4}{1-\sqrt{x}}[/tex]. If the function is not invertible, enter NONE.

[tex]g^{-1}(x)= \boxed{\text{Write your inverse function in terms of the independent variable } x.}[/tex]



Answer :

To find the inverse function of [tex]\( g(x) = \frac{\sqrt{x} + 4}{1 - \sqrt{x}} \)[/tex], follow these steps:

### Step 1: Express the function in terms of [tex]\( y \)[/tex]

Let [tex]\( y = g(x) \)[/tex]. Thus,
[tex]\[ y = \frac{\sqrt{x} + 4}{1 - \sqrt{x}} \][/tex]

### Step 2: Solve for [tex]\( \sqrt{x} \)[/tex] in terms of [tex]\( y \)[/tex]

1. Multiply both sides by [tex]\( (1 - \sqrt{x}) \)[/tex] to get rid of the denominator:
[tex]\[ y(1 - \sqrt{x}) = \sqrt{x} + 4 \][/tex]

2. Distribute [tex]\( y \)[/tex] to both terms in the parentheses:
[tex]\[ y - y \sqrt{x} = \sqrt{x} + 4 \][/tex]

3. Rearrange the equation to collect all terms involving [tex]\( \sqrt{x} \)[/tex] on one side:
[tex]\[ y - 4 = y \sqrt{x} + \sqrt{x} \][/tex]
[tex]\[ y - 4 = \sqrt{x}(y + 1) \][/tex]

4. Solve for [tex]\( \sqrt{x} \)[/tex]:
[tex]\[ \sqrt{x} = \frac{y - 4}{y + 1} \][/tex]

### Step 3: Square both sides to solve for [tex]\( x \)[/tex]

[tex]\[ x = \left(\frac{y - 4}{y + 1}\right)^2 \][/tex]

### Step 4: Replace [tex]\( y \)[/tex] with [tex]\( x \)[/tex]

To write the inverse function, replace [tex]\( y \)[/tex] with [tex]\( x \)[/tex]:
[tex]\[ g^{-1}(x) = \left(\frac{x - 4}{x + 1}\right)^2 \][/tex]

Thus, the inverse function of [tex]\( g(x) = \frac{\sqrt{x} + 4}{1 - \sqrt{x}} \)[/tex] is:
[tex]\[ g^{-1}(x) = \left( \frac{x - 4}{x + 1} \right)^2 \][/tex]