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Behaviors of Implicit Relations

David Brown

David Brown

7 min read

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Study Guide Overview

This study guide covers critical points of implicit relations, including how to identify them by finding where the derivative is zero or undefined. It explains finding horizontal and vertical tangents using the first derivative. The guide also demonstrates classifying critical points (local minima, maxima, inflection points) using the second derivative and provides worked examples and practice questions.

Critical Points of Implicit Relations

Table of Contents

  1. Introduction to Critical Points
  2. Identifying Critical Points in Implicit Equations
  3. Horizontal and Vertical Tangents
  4. Worked Example
  5. Practice Questions
  6. Glossary
  7. Summary and Key Takeaways

Introduction to Critical Points

Critical points are crucial in determining the behavior of functions. They are points on the graph of a function where the derivative is zero or undefined. These points help in identifying local maxima, local minima, and points of inflection.

Identifying Critical Points in Implicit Equations

Implicit equations can have critical points, which are defined similarly to those in explicit functions.

Key Concepts

Key Concept

Critical Point: A point where the derivative of the function is either zero or does not exist.

The application of first and second derivatives to classify the nature of points on a graph can be extended to implicit functions.

Classifying Critical Points

Here is a summary of how the first and second derivatives are used to classify critical points:

Type of PointFirst DerivativeSecond Derivative
Local MinimumZeroPositive or zero
Local MaximumZeroNegative or zero
Point of Inflection (Critical)ZeroZero
Point of Inflection (Non-critical)Non-zeroZero
Common Mistake

Second derivative equal to zero is not enough for a point to be a point of inflection. The second derivative must change sign at the point as well.

Horizontal and Vertical Tangents...

Question 1 of 8

What is a critical point of a function? 🤔

A point where the function equals zero

A point where the derivative of the function is zero or undefined

A point where the second derivative is zero

A point where the function has a positive value