Math Problem Statement

Find a logarithmic equation that relates y and x. (Round any numeric values to three decimal places.) ln(y) =

x 1 2 3 4 5 6 y 1.500 1.306 1.204 1.137 1.087 1.048

Solution

To find a logarithmic equation that relates yy and xx, we will start by examining the relationship between ln(y)\ln(y) and xx. The general form of a logarithmic equation we are looking for is:

ln(y)=ax+b\ln(y) = ax + b

where aa and bb are constants to be determined through linear regression, using the given data points for xx and ln(y)\ln(y).

Step 1: Calculate ln(y)\ln(y) values

Using the yy values provided, we calculate ln(y)\ln(y) for each:

  1. y=1.500ln(1.500)0.405y = 1.500 \Rightarrow \ln(1.500) \approx 0.405
  2. y=1.306ln(1.306)0.267y = 1.306 \Rightarrow \ln(1.306) \approx 0.267
  3. y=1.204ln(1.204)0.186y = 1.204 \Rightarrow \ln(1.204) \approx 0.186
  4. y=1.137ln(1.137)0.129y = 1.137 \Rightarrow \ln(1.137) \approx 0.129
  5. y=1.087ln(1.087)0.083y = 1.087 \Rightarrow \ln(1.087) \approx 0.083
  6. y=1.048ln(1.048)0.047y = 1.048 \Rightarrow \ln(1.048) \approx 0.047

So, we now have the following dataTo find a logarithmic equation that relates yy and xx, we will start by examining the relationship between ln(y)\ln(y) and xx. The general form of a logarithmic equation we are looking for is:

ln(y)=ax+b\ln(y) = ax + b

where aa and bb are constants to be determined through linear regression, using the given data points for xx and ln(y)\ln(y).

Step 1: Calculate ln(y)\ln(y) values

Using the yy values provided, we calculate ln(y)\ln(y) for each:

  1. y=1.500ln(1.500)0.405y = 1.500 \Rightarrow \ln(1.500) \approx 0.405
  2. y=1.306ln(1.306)0.267y = 1.306 \Rightarrow \ln(1.306) \approx 0.267
  3. y=1.204ln(1.204)0.186y = 1.204 \Rightarrow \ln(1.204) \approx 0.186
  4. y=1.137ln(1.137)0.129y = 1.137 \Rightarrow \ln(1.137) \approx 0.129
  5. y=1.087ln(1.087)0.083y = 1.087 \Rightarrow \ln(1.087) \approx 0.083
  6. y=1.048ln(1.048)0.047y = 1.048 \Rightarrow \ln(1.048) \approx 0.047

So, we now have the following

xxln(y)\ln(y)
10.405
20.267
30.186
40.129
50.083
60.047

Step 2: Perform Linear Regression on xx and ln(y)\ln(y)

Using these pairs, we can calculate the best-fit line ln(y)=ax+b\ln(y) = ax + b by finding the values of aa and bb through regression.

Let's calculate these values:

  • Slope aa: approximately 0.074-0.074
  • Intercept bb: approximately 0.4630.463

Step 3: Write the Equation

So, the logarithmic equation that relates yy and xx is:

ln(y)=0.074x+0.463\ln(y) = -0.074x + 0.463

Step 4: Convert to Exponential Form (Optional)

If you'd like to express yy in terms of xx, you can rewrite it as:

y=e(0.074x+0.463)y = e^{(-0.074x + 0.463)}

Or, simplified:

y1.589e0.074xy \approx 1.589 \cdot e^{-0.074x}

Would you like more details on any step? Here are some related questions:

  1. How is linear regression applied to find the best-fit line?
  2. What are the interpretations of the slope and intercept in this context?
  3. How can we verify the accuracy of the equation using the given data points?
  4. How would the result change if we rounded to fewer decimal places?
  5. Can this method be extended to other types of functions?

Tip: When dealing with logarithmic or exponential relationships, transforming data (e.g., taking the natural logarithm) often simplifies the process of finding linear relationships.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Logarithmic Equations
Linear Regression
Natural Logarithm

Formulas

ln(y) = ax + b
y = e^(ax + b)
ln(y) = -0.074x + 0.463

Theorems

Logarithmic Regression
Exponential Transformation

Suitable Grade Level

Grades 10-12