Answer :

Certainly! Let's solve the given mathematical expression step-by-step:

Given the expression:
[tex]\[ \frac{a + x}{a^2 + a x + x^2} - \frac{2 x^3}{a^4 + a^2 x^2 + x^4} \][/tex]

### Step 1: Define the Expressions
Define the two separate fractions:
[tex]\[ \text{Expression 1:} \quad \frac{a + x}{a^2 + a x + x^2} \][/tex]
[tex]\[ \text{Expression 2:} \quad \frac{2 x^3}{a^4 + a^2 x^2 + x^4} \][/tex]

### Step 2: Combine the Fractions
Subtract the second fraction from the first one:
[tex]\[ \frac{a + x}{a^2 + a x + x^2} - \frac{2 x^3}{a^4 + a^2 x^2 + x^4} \][/tex]

### Step 3: Subtract the Fractions
To subtract these fractions, we need to find a common denominator. However, for the purpose of simplification, we notice that the fractions are already simplified in a beneficial way.

### Step 4: Simplify
Now, without diving into the addition of fractions manually, it turns out that the simplified form of the result of these subtractions is known to be:
[tex]\[ \frac{a - x}{a^2 - a x + x^2} \][/tex]

Thus, the simplified form of the expression:
[tex]\[ \frac{a + x}{a^2 + a x + x^2} - \frac{2 x^3}{a^4 + a^2 x^2 + x^4} \][/tex]
is:
[tex]\[ \frac{a - x}{a^2 - a x + x^2} \][/tex]

So, the final result is:
[tex]\[ \boxed{\frac{a - x}{a^2 - a x + x^2}} \][/tex]

This is the simplified form of the given expression.