For the function y = f(x) = x² – 2x, x x ≥ 1, find (ƒ-¹) '(3) = df-1 dy y=3

Calculus: Early Transcendentals
8th Edition
ISBN:9781285741550
Author:James Stewart
Publisher:James Stewart
Chapter1: Functions And Models
Section: Chapter Questions
Problem 1RCC: (a) What is a function? What are its domain and range? (b) What is the graph of a function? (c) How...
icon
Related questions
Question
### Calculus Problem - Finding the derivative of the inverse function

**Problem Statement:**

For the function \( y = f(x) = x^2 - 2x \), where \( x \geq 1 \), find:

\[
\left. \frac{d f^{-1}}{dy} \right|_{y=3}
\]

**Solution:**
### Finding the Derivative:

We need to find \( \left( f^{-1} \right)'(3) \), which represents the derivative of the inverse function evaluated at \( y=3 \).

1. **Inverse Function Derivative Formula**:
   
   The derivative of the inverse function \( f^{-1}(x) \) at the point \( y \) is given by:

   \[
   \left( f^{-1} \right)'(y) = \frac{1}{f'(f^{-1}(y))}
   \]

2. **Evaluate \( f^{-1}(3) \)**:
   
   We need to find the \( x \) value such that \( f(x) = 3 \):
   
   \[
   x^2 - 2x = 3
   \]
   
   Rearrange and solve for \( x \):
   
   \[
   x^2 - 2x - 3 = 0
   \]
   
   Factoring the quadratic equation:
   
   \[
   (x-3)(x+1) = 0
   \]
   
   Therefore, \( x = 3 \) or \( x = -1 \). Given the constraint \( x \geq 1 \), we select \( x = 3 \).

3. **Find \( f'(x) \)**:
   
   Compute the derivative \( f'(x) \) of \( f(x) \):
   
   \[
   f(x) = x^2 - 2x
   \]
   
   Differentiate with respect to \( x \):
   
   \[
   f'(x) = 2x - 2
   \]
   
   Evaluate \( f'(x) \) at \( x = 3 \):
   
   \[
   f'(3) = 2(3) - 2 = 6 - 2 = 4
   \]

4. **Substitute in the Inverse Derivative Formula**:
   
   \[
Transcribed Image Text:### Calculus Problem - Finding the derivative of the inverse function **Problem Statement:** For the function \( y = f(x) = x^2 - 2x \), where \( x \geq 1 \), find: \[ \left. \frac{d f^{-1}}{dy} \right|_{y=3} \] **Solution:** ### Finding the Derivative: We need to find \( \left( f^{-1} \right)'(3) \), which represents the derivative of the inverse function evaluated at \( y=3 \). 1. **Inverse Function Derivative Formula**: The derivative of the inverse function \( f^{-1}(x) \) at the point \( y \) is given by: \[ \left( f^{-1} \right)'(y) = \frac{1}{f'(f^{-1}(y))} \] 2. **Evaluate \( f^{-1}(3) \)**: We need to find the \( x \) value such that \( f(x) = 3 \): \[ x^2 - 2x = 3 \] Rearrange and solve for \( x \): \[ x^2 - 2x - 3 = 0 \] Factoring the quadratic equation: \[ (x-3)(x+1) = 0 \] Therefore, \( x = 3 \) or \( x = -1 \). Given the constraint \( x \geq 1 \), we select \( x = 3 \). 3. **Find \( f'(x) \)**: Compute the derivative \( f'(x) \) of \( f(x) \): \[ f(x) = x^2 - 2x \] Differentiate with respect to \( x \): \[ f'(x) = 2x - 2 \] Evaluate \( f'(x) \) at \( x = 3 \): \[ f'(3) = 2(3) - 2 = 6 - 2 = 4 \] 4. **Substitute in the Inverse Derivative Formula**: \[
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps with 2 images

Blurred answer
Recommended textbooks for you
Calculus: Early Transcendentals
Calculus: Early Transcendentals
Calculus
ISBN:
9781285741550
Author:
James Stewart
Publisher:
Cengage Learning
Thomas' Calculus (14th Edition)
Thomas' Calculus (14th Edition)
Calculus
ISBN:
9780134438986
Author:
Joel R. Hass, Christopher E. Heil, Maurice D. Weir
Publisher:
PEARSON
Calculus: Early Transcendentals (3rd Edition)
Calculus: Early Transcendentals (3rd Edition)
Calculus
ISBN:
9780134763644
Author:
William L. Briggs, Lyle Cochran, Bernard Gillett, Eric Schulz
Publisher:
PEARSON
Calculus: Early Transcendentals
Calculus: Early Transcendentals
Calculus
ISBN:
9781319050740
Author:
Jon Rogawski, Colin Adams, Robert Franzosa
Publisher:
W. H. Freeman
Precalculus
Precalculus
Calculus
ISBN:
9780135189405
Author:
Michael Sullivan
Publisher:
PEARSON
Calculus: Early Transcendental Functions
Calculus: Early Transcendental Functions
Calculus
ISBN:
9781337552516
Author:
Ron Larson, Bruce H. Edwards
Publisher:
Cengage Learning