Answer :

Let's simplify the given expression step by step:

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

### Step 1: Simplify the numerator

The numerator of the expression is:

[tex]\[ \frac{1}{x} + \frac{1}{y} \][/tex]

To combine the fractions, we need a common denominator. The common denominator between [tex]\(x\)[/tex] and [tex]\(y\)[/tex] is [tex]\(xy\)[/tex]:

[tex]\[ \frac{1}{x} + \frac{1}{y} = \frac{y}{xy} + \frac{x}{xy} = \frac{y + x}{xy} \][/tex]

So, the simplified numerator is:

[tex]\[ \frac{y + x}{xy} \][/tex]

### Step 2: Simplify the denominator

The denominator of the expression is:

[tex]\[ \frac{x}{y} - \frac{y}{x} \][/tex]

To combine these fractions, we also need a common denominator. The common denominator between [tex]\(y\)[/tex] and [tex]\(x\)[/tex] is [tex]\(xy\)[/tex]:

[tex]\[ \frac{x}{y} = \frac{x^2}{xy}, \quad \frac{y}{x} = \frac{y^2}{xy} \][/tex]

Thus, the denominator becomes:

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

### Step 3: Combine the simplified numerator and denominator

Now we rewrite the original expression using the simplified numerator and denominator:

[tex]\[ \frac{\frac{y + x}{xy}}{\frac{x^2 - y^2}{xy}} \][/tex]

This can be written as:

[tex]\[ \frac{y + x}{xy} \div \frac{x^2 - y^2}{xy} \][/tex]

Dividing by a fraction is the same as multiplying by its reciprocal:

[tex]\[ \frac{y + x}{xy} \times \frac{xy}{x^2 - y^2} \][/tex]

Notice that [tex]\(xy\)[/tex] in the numerator of the second fraction and denominators cancel out:

[tex]\[ \frac{y + x}{\cancel{xy}} \times \frac{\cancel{xy}}{x^2 - y^2} = \frac{y + x}{x^2 - y^2} \][/tex]

### Step 4: Simplify the resulting expression

Recognize that [tex]\(x^2 - y^2\)[/tex] can be factored as a difference of squares:

[tex]\[ x^2 - y^2 = (x + y)(x - y) \][/tex]

Thus, our expression becomes:

[tex]\[ \frac{y + x}{(x + y)(x - y)} \][/tex]

Since [tex]\(y + x\)[/tex] is the same as [tex]\(x + y\)[/tex], they cancel out:

[tex]\[ \frac{x + y}{(x + y)(x - y)} = \frac{1}{x - y} \][/tex]

So the final simplified expression is:

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