Find the derivative of the constant function `f(x) = a`for a fixed real number a.

Explanation

To find the derivative of the constant function \( f(x) = a \) where \( a \) is a fixed real number, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Derivative**:
The derivative of a function \( f(x) \) at a point \( x \) is defined as:
\[
f'(x) = \lim_{h \to 0} \frac{f(x + h) - f(x)}{h}
...