Students need to explain why a function, comparison, or feature claim is valid.
Error analysis
Identify whether a claim uses the function rule correctly.
Feature comparison
Compare intercepts, maximums, minimums, and values.
Representation choice
Use the form that reveals the needed feature.
Long-term behavior
Compare linear and exponential growth for large inputs.
Practice Questions
Function Analysis and Error Correction
Check your answer first, then reveal the explanation when you want the model.
Question 1
Critique reasoning
A student says \{(1,4),(2,4),(3,4)\} is not a function because the output 4 repeats. What is the best response?
Question 2
Compare features
Function A is A(x)=2x+6. Function B is shown in the graph. Which statement is true?
Function B
Question 3
Reasonable domain
A function models the number of students left in a gym after m minutes. Why might the domain be restricted?
Question 4
Compare function families
Function A is linear and increases by 5 each step. Function B is exponential and doubles each step. Both start at 10. Which statement is most reasonable for large positive inputs?
Question 5
Error analysis
A student finds f(3) for f(x)=x^2+4 by doing 3^2+4=13. What should you say?
Question 6
Compare maximums
Function A has vertex (2,9) and opens downward. Function B has vertex (-1,7) and opens downward. Which statement is true?
Question 7
Representation choice
You need to find the zeros of q(x)=2(x-4)(x+1). Why is this form useful?
Question 8
Compare values
Function A is A(x)=x^2-2. Function B is B(x)=3x+2. Which function has the greater value at x=4?
Question 9
Correct comparison
Function A is A(x)=x^2-2. Function B is B(x)=3x+2. Which function has the greater value at x=5?