Table of contents
- 0. Functions7h 52m
- Introduction to Functions16m
- Piecewise Functions10m
- Properties of Functions9m
- Common Functions1h 8m
- Transformations5m
- Combining Functions27m
- Exponent rules32m
- Exponential Functions28m
- Logarithmic Functions24m
- Properties of Logarithms34m
- Exponential & Logarithmic Equations35m
- Introduction to Trigonometric Functions38m
- Graphs of Trigonometric Functions44m
- Trigonometric Identities47m
- Inverse Trigonometric Functions48m
- 1. Limits and Continuity2h 2m
- 2. Intro to Derivatives1h 33m
- 3. Techniques of Differentiation3h 18m
- 4. Applications of Derivatives2h 38m
- 5. Graphical Applications of Derivatives6h 2m
- 6. Derivatives of Inverse, Exponential, & Logarithmic Functions2h 37m
- 7. Antiderivatives & Indefinite Integrals1h 26m
- 8. Definite Integrals3h 25m
3. Techniques of Differentiation
Product and Quotient Rules
Problem 3.R.35
Textbook Question
Evaluate and simplify y'.
y = 4u²+u / 8u+1

1
First, identify the expression given: \( y' \cdot y = \frac{4u^2 + u}{8u + 1} \). This is a differential equation involving \( y' \), the derivative of \( y \) with respect to \( u \).
To simplify the expression, consider factoring the numerator \( 4u^2 + u \). Notice that \( u \) is a common factor, so factor it out: \( u(4u + 1) \).
Next, check if the expression can be simplified further by canceling common factors in the numerator and denominator. The denominator is \( 8u + 1 \), which does not share any common factors with the numerator after factoring.
Now, consider the context of the problem. If \( y' \cdot y \) represents a derivative, you might need to separate variables or integrate to solve for \( y \). However, without additional context, focus on simplifying the algebraic expression.
Finally, ensure the expression is in its simplest form. Since no further simplification is possible, the expression remains \( \frac{u(4u + 1)}{8u + 1} \).
Recommended similar problem, with video answer:

This video solution was recommended by our tutors as helpful for the problem above
Video duration:
5mPlay a video:
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Derivative
The derivative of a function measures how the function's output value changes as its input value changes. It is a fundamental concept in calculus, representing the slope of the tangent line to the curve at any given point. In this context, we need to apply the rules of differentiation to find y', the derivative of the function y with respect to u.
Recommended video:
Derivatives
Quotient Rule
The quotient rule is a formula used to differentiate functions that are expressed as the ratio of two other functions. If y = f(u)/g(u), the derivative y' is given by (f' * g - f * g') / g². This rule is essential for the given problem since y is defined as a fraction, and applying the quotient rule will allow us to find the derivative correctly.
Recommended video:
The Quotient Rule
Simplification
Simplification in calculus involves reducing an expression to its most basic form, making it easier to interpret or compute. After finding the derivative using the quotient rule, we may need to combine like terms, factor, or cancel common factors to present the result in a clearer and more concise manner. This step is crucial for ensuring the final answer is both accurate and easy to understand.
Recommended video:
The Product Rule Example 2
Related Videos
Related Practice