For each of the following functions, evaluate the derivative at the indicated value (s) :
`f(x)=99x,x=100`

Answer

To evaluate the derivative of the function \( f(x) = 99x \) at \( x = 100 \), we will follow these steps:

### Step 1: Identify the function
The given function is:
\[ f(x) = 99x \]

### Step 2: Differentiate the function
To find the derivative \( f'(x) \), we differentiate \( f(x) \) with respect to \( x \):
\[ f'(x) = \frac{d}{dx}(99x) \]
Since 99 is a constant, we can apply the constant multiple rule of differentiation:
\[ f'(x) = 99 \cdot \frac{d}{dx}(x) \]
The derivative of \( x \) with respect to \( x \) is 1:
\[ f'(x) = 99 \cdot 1 = 99 \]

### Step 3: Evaluate the derivative at \( x = 100 \)
Now, we need to evaluate \( f'(x) \) at \( x = 100 \):
\[ f'(100) = 99 \]

### Conclusion
Thus, the value of the derivative \( f'(x) \) at \( x = 100 \) is:
\[ \boxed{99} \]

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