Math Problem Statement

Starting with the graph of y = e^(-x), find the equation of the function whose graph results from the following transformations: (a) reflecting about the line y = 6, (b) shifting 8 units to the right, (c) reflecting about the line x = 3, (d) shifting up 7 units.

Solution

Let's go through the problem step by step based on the image you've provided, which deals with the function y=exy = e^{-x}.

Problem #13: Transformations of y=exy = e^{-x}

We are asked to apply several transformations to the given function and find the new equations.


(a) Reflecting about the line y=6y = 6:

When reflecting about the line y=6y = 6, we perform a vertical reflection around this line. The formula for reflecting y=f(x)y = f(x) about y=ky = k is:

ynew=2kf(x)y_{\text{new}} = 2k - f(x)

Here, k=6k = 6, and f(x)=exf(x) = e^{-x}. Thus, the transformation gives:

ynew=2(6)ex=12exy_{\text{new}} = 2(6) - e^{-x} = 12 - e^{-x}

You already entered this correctly.


(b) Shifting 8 units to the right:

A horizontal shift of a function f(x)f(x) by hh units to the right is given by the formula:

ynew=f(xh)y_{\text{new}} = f(x - h)

In this case, h=8h = 8. So the transformed equation becomes:

ynew=e(x8)=e(x8)y_{\text{new}} = e^{-(x - 8)} = e^{-(x - 8)}


(c) Reflecting about the line x=3x = 3:

To reflect about the line x=3x = 3, the transformation involves flipping the graph horizontally around this line. The formula for reflecting f(x)f(x) about x=hx = h is:

ynew=f(2hx)y_{\text{new}} = f(2h - x)

Here, h=3h = 3, so the transformation gives:

ynew=e(2(3)x)=e(6x)=ex6y_{\text{new}} = e^{-(2(3) - x)} = e^{-(6 - x)} = e^{x - 6}


(d) Shifting up 7 units:

A vertical shift by kk units upwards for the function f(x)f(x) is given by:

ynew=f(x)+ky_{\text{new}} = f(x) + k

In this case, k=7k = 7, so the new equation becomes:

ynew=ex+7y_{\text{new}} = e^{-x} + 7


Summary of Answers:

  • (a) 12ex12 - e^{-x} (this was already correct)
  • (b) e(x8)e^{-(x - 8)}
  • (c) ex6e^{x - 6}
  • (d) ex+7e^{-x} + 7

Would you like me to explain any of these transformations in more detail?


Here are 5 related questions to consider:

  1. What happens when you reflect about the x-axis instead of the y-axis?
  2. How would a vertical stretch affect the function y=exy = e^{-x}?
  3. What is the result of shifting the function y=exy = e^{-x} down by 5 units?
  4. How would you reflect a function about the line y=0y = 0?
  5. What happens to the domain and range of y=exy = e^{-x} after a horizontal shift?

Tip: Always remember that horizontal transformations affect the input xx, while vertical transformations affect the entire output f(x)f(x).

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Exponential Functions
Graph Transformations

Formulas

Vertical reflection formula: y_new = 2k - f(x)
Horizontal shift: y_new = f(x - h)
Horizontal reflection: y_new = f(2h - x)
Vertical shift: y_new = f(x) + k

Theorems

-

Suitable Grade Level

Grades 10-12