Exercises for Question Type 13: Formulating and plotting exponential models to indicate key features such as asymptotes and intercepts - IB | RevisionDojo
A population of fish is modelled by P(t)=50e0.08t, where t is in years. Graph P(t) for 0≤t≤50, indicating the horizontal asymptote, initial population, and population at t=50.
Question 2
Skill question
The temperature of a cooling object is modelled by T(t)=20+80e−0.15t where t is in minutes. Sketch its graph, stating the horizontal asymptote and the initial temperature.
Question 3
Skill question
The half-life of a radioactive isotope is 5 days, with initial mass 100 g. Model the mass as M(t)=100⋅2−t/5. Graph M(t) for 0≤t≤20, finding asymptote and mass at t=20.
Question 4
Skill question
Sketch the graph of the exponential function f(x)=3⋅2x−1−4. On your sketch, clearly indicate the horizontal asymptote and the x- and y-intercepts.
Question 5
Skill question
A bank account grows continuously at 5% annual interest. If A(t)=1000e0.05t, sketch A(t), indicating asymptote, initial amount, and amount after 20 years.
Question 6
Skill question
A medication concentration in blood follows C(t)=C0e−0.25t. If the initial concentration is 200 mg/L, sketch C(t), specify the horizontal asymptote, and compute the concentration after 10 hours.
Question 7
Skill question
An aquarium’s pH level increases following the model pH(t)=6+2(1−e−0.3t). Graph pH(t) for 0≤t≤20, stating horizontal asymptote and initial value.
Question 8
Skill question
Find and sketch the exponential model of the form y=A⋅3x+C that passes through the points (0,5) and (1,14). Indicate the asymptote and intercepts.
Question 9
Skill question
Given the graph of an exponential function with horizontal asymptote y=2 and passing through (0,5) and (2,10), find its equation in the form f(x)=A⋅bx+2 and sketch the graph.
Question 10
Skill question
Determine and sketch the exponential function of the form f(x)=A⋅bx+D given that its horizontal asymptote is y=3, it passes through (0,7) and its growth factor is 1.5 per unit increase in x. Indicate intercepts.
Question 11
Skill question
Fit an exponential model y=Aekx to the data points (1,5) and (4,40). Then sketch the graph, indicating asymptote and intercept.