Answer
To find the derivative of \( \frac{2x^3 + 3x}{x^2 - 5} \) using the quotient rule:
1. **Identify**:
- \( g(x) = 2x^3 + 3x \)
- \( h(x) = x^2 - 5 \)
2. **Differentiate**:
- \( g'(x) = 6x^2 + 3 \)
- \( h'(x) = 2x \)
3. **Apply the Quotient Rule**:
\[
f'(x) = \frac{(6x^2 + 3)(x^2 - 5) - (2x^3 + 3x)(2x)}{(x^2 - 5)^2}
\]
4. **Simplify**:
\[
f'(x) = \frac{2x^4 - 33x^2 - 15}{(x^2 - 5)^2}
\]
So, the derivative is \( \frac{2x^4 - 33x^2 - 15}{(x^2 - 5)^2} \).
Solution
Certainly! The **quotient rule** is a fundamental technique in calculus used to find the derivative of a function that is the ratio of two differentiable functions.
### Quotient Rule Formula
If you have a function \( f(x) \) defined as:
\[
f(x) = \frac{g(x)}{h(x)}
\]
where both \( g(x) \) and \( h(x) \) are differentiable functions, then the derivative of \( f(x) \), denoted as \( f'(x) \), is given by:
\[
f'(x) = \frac{g'(x) \cdot h(x) - g(x) \cdot h'(x)}{[h(x)]^2}
\]
### Step-by-Step Application
Let's walk through the steps to apply the quotient rule with an example.
**Example:**
Differentiate the function
\[
f(x) = \frac{2x^3 + 3x}{x^2 - 5}
\]
**Step 1: Identify \( g(x) \) and \( h(x) \)**
\[
g(x) = 2x^3 + 3x \\
h(x) = x^2 - 5
\]
**Step 2: Find the derivatives \( g'(x) \) and \( h'(x) \)**
\[
g'(x) = \frac{d}{dx}(2x^3 + 3x) = 6x^2 + 3 \\
h'(x) = \frac{d}{dx}(x^2 - 5) = 2x
\]
**Step 3: Apply the Quotient Rule Formula**
\[
f'(x) = \frac{(6x^2 + 3)(x^2 - 5) - (2x^3 + 3x)(2x)}{(x^2 - 5)^2}
\]
**Step 4: Simplify the Expression**
First, expand the numerator:
\[
(6x^2 + 3)(x^2 - 5) = 6x^4 - 30x^2 + 3x^2 - 15 = 6x^4 - 27x^2 - 15
\]
\[
(2x^3 + 3x)(2x) = 4x^4 + 6x^2
\]
Subtract the second product from the first:
\[
6x^4 - 27x^2 - 15 - (4x^4 + 6x^2) = 2x^4 - 33x^2 - 15
\]
So, the derivative is:
\[
f'(x) = \frac{2x^4 - 33x^2 - 15}{(x^2 - 5)^2}
\]
### Summary
To **divide** an expression using the **quotient rule**:
1. **Identify** the numerator function \( g(x) \) and the denominator function \( h(x) \).
2. **Differentiate** both \( g(x) \) and \( h(x) \) to find \( g'(x) \) and \( h'(x) \).
3. **Apply** the quotient rule formula:
\[
f'(x) = \frac{g'(x)h(x) - g(x)h'(x)}{[h(x)]^2}
\]
4. **Simplify** the resulting expression as needed.
If you have a specific expression you'd like to work through, feel free to share it, and I can guide you through the process!
Reviewed and approved by the UpStudy tutoring team
Explain
Simplify this solution