Questions: For the scatterplot on the right, determine which, if any, of these functions might be used as a model for the data.
Quadratic: f(x)=a x^2+b x+c
Polynomial, not quadratic
Exponential: f(x)=a e^(k x), k>0
Exponential: f(x)=a e^(-k x), k>0
Logarithmic: f(x)=a+b ln x
Logistic: f(x)=a/(1+b e^(-k x))
Which of the functions above might be used as a model for the data?
A. Exponential: f(x)=a e^(-k x), k>0
B. Logarithmic: f(x)=a+b ln x
C. Logistic: f(x)=a/(1+b e^(-k x))
D. Quadratic: f(x)=a x^2+b x+c
E. Polynomial, not quadratic
F. Exponential: f(x)=a e^(k x), k>0
Transcript text: For the scatterplot on the right, determine which, if any, of these functions might be used as a model for the data.
Quadratic: $f(x)=a x^{2}+b x+c$
Polynomial, not quadratic
Exponential: $f(x)=a e^{k x}, k>0$
Exponential: $f(x)=a e^{-k x}, k>0$
Logarithmic: $f(x)=a+b \ln x$
Logistic: $f(x)=\frac{a}{1+b e^{-k x}}$
Which of the functions above might be used as a model for the data?
A. Exponential: $f(x)=a e^{-k x}, \mathrm{k}>0$
B. Logarithmic: $f(x)=a+b \ln x$
C. Logistic: $f(x)=\frac{a}{1+b e^{-k x}}$
D. Quadratic: $f(x)=a x^{2}+b x+c$
E. Polynomial, not quadratic
F. Exponential: $f(x)=a e^{k x}, k>0$
Solution
Solution Steps
Step 1: Identify the type of data trend
Examine the scatterplot to determine the trend of the data. The data points show a decreasing trend that levels off as the x-values increase.
Step 2: Match the trend with function types
Compare the observed trend with the given function types:
Exponential: Decreases rapidly and then levels off.
Logarithmic: Increases rapidly and then levels off.
Logistic: S-shaped curve, levels off at both ends.
Quadratic: Parabolic shape, either opens upwards or downwards.
Polynomial, not quadratic: Various shapes, not necessarily fitting the observed trend.
Step 3: Select the appropriate function
The scatterplot shows a decreasing trend that levels off, which matches the behavior of an exponential function.