Calculus: Early Transcendentals
Calculus: Early Transcendentals
8th Edition
ISBN: 9781285741550
Author: James Stewart
Publisher: Cengage Learning
Bartleby Related Questions Icon

Related questions

Question
### Problem 8: Conic Section Equation

**Problem Statement:**
Find the equation of the conic whose focus is \((4, -5)\) and directrix is \(x = -2\).

**Explanation:**
To determine the type of conic section and its equation, we use the definition of a conic section: the set of all points \((x, y)\) such that the ratio of the distance from \((x, y)\) to the focus to the distance from \((x, y)\) to the directrix is constant.

In this case:
- **Focus:** \((4, -5)\)
- **Directrix:** \(x = -2\)

The standard form of the equation for a conic section is determined by the given information and adjusting for different conic shapes (ellipses, parabolas, hyperbolas).

#### Step-by-Step Solution:

1. **Identify the conic type:**
   Since we have one focus and one directrix, this indicates that the conic is a parabola.

2. **Parabola Equation (Vertex Form):**
   A parabola's equation with focus \((h, k)\) and directrix \(x = h - p\) (if the directrix is vertical) can be written as:
   \[
   (x - h)^2 = 4p(y - k)
   \]

   Here, the vertex \((h, k)\) of the parabola is the midpoint between the focus and the directrix.

3. **Calculate \(h\), \(k\), and \(p\):**
   - \(h = 4\)
   - \(k = -5\)
   - Distance from the focus to the directrix: \(4 - (-2) = 6\)
   - Half of this distance is the vertex distance from the directrix:
     \(p = \frac{6}{2} = 3\)

4. **Formulate the equation:**
   Since the directrix \(x = -2\) is vertical, the equation for the parabola is formed using this value of \(p\):
   \[
   (x - 4)^2 = 4(3)(y + 5)
   \]
   Simplifying:
   \[
   (x - 4)^2 = 12(y + 5)
   \]
expand button
Transcribed Image Text:### Problem 8: Conic Section Equation **Problem Statement:** Find the equation of the conic whose focus is \((4, -5)\) and directrix is \(x = -2\). **Explanation:** To determine the type of conic section and its equation, we use the definition of a conic section: the set of all points \((x, y)\) such that the ratio of the distance from \((x, y)\) to the focus to the distance from \((x, y)\) to the directrix is constant. In this case: - **Focus:** \((4, -5)\) - **Directrix:** \(x = -2\) The standard form of the equation for a conic section is determined by the given information and adjusting for different conic shapes (ellipses, parabolas, hyperbolas). #### Step-by-Step Solution: 1. **Identify the conic type:** Since we have one focus and one directrix, this indicates that the conic is a parabola. 2. **Parabola Equation (Vertex Form):** A parabola's equation with focus \((h, k)\) and directrix \(x = h - p\) (if the directrix is vertical) can be written as: \[ (x - h)^2 = 4p(y - k) \] Here, the vertex \((h, k)\) of the parabola is the midpoint between the focus and the directrix. 3. **Calculate \(h\), \(k\), and \(p\):** - \(h = 4\) - \(k = -5\) - Distance from the focus to the directrix: \(4 - (-2) = 6\) - Half of this distance is the vertex distance from the directrix: \(p = \frac{6}{2} = 3\) 4. **Formulate the equation:** Since the directrix \(x = -2\) is vertical, the equation for the parabola is formed using this value of \(p\): \[ (x - 4)^2 = 4(3)(y + 5) \] Simplifying: \[ (x - 4)^2 = 12(y + 5) \]
Expert Solution
Check Mark
Knowledge Booster
Background pattern image
Calculus
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, calculus and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Text book image
Calculus: Early Transcendentals
Calculus
ISBN:9781285741550
Author:James Stewart
Publisher:Cengage Learning
Text book image
Thomas' Calculus (14th Edition)
Calculus
ISBN:9780134438986
Author:Joel R. Hass, Christopher E. Heil, Maurice D. Weir
Publisher:PEARSON
Text book image
Calculus: Early Transcendentals (3rd Edition)
Calculus
ISBN:9780134763644
Author:William L. Briggs, Lyle Cochran, Bernard Gillett, Eric Schulz
Publisher:PEARSON
Text book image
Calculus: Early Transcendentals
Calculus
ISBN:9781319050740
Author:Jon Rogawski, Colin Adams, Robert Franzosa
Publisher:W. H. Freeman
Text book image
Precalculus
Calculus
ISBN:9780135189405
Author:Michael Sullivan
Publisher:PEARSON
Text book image
Calculus: Early Transcendental Functions
Calculus
ISBN:9781337552516
Author:Ron Larson, Bruce H. Edwards
Publisher:Cengage Learning