AP® Precalculus · Free response

A table, a cubic and an inverse

write it first, then score yourself point by point

Q1: Function Concepts · Part A: graphing calculator allowed · 6 points

The question

Name: ______________________   Date: ____________   A table, a cubic and an inverse (6 points)

Table

Values of ff, and the function gg

The table gives values of the function ff at selected inputs. The function gg is defined by g(x)=0.5x3−2x+1g(x) = 0.5x^3 - 2x + 1 for every real number xx.
Values of the function f at x = -2, -1, 0, 1, 2, 3 and 4
xx-2-101234
f(x)f(x)52-13620
  1. (A(i)) Find the value of f(g(2))f(g(2)), or indicate that it cannot be found from the information given. Show the work that leads to your answer. [1 point]

  2. (A(ii)) Find every value of xx in the table for which f(x)=2f(x) = 2. [1 point]

  3. (B(i)) Find every value of xx for which g(x)=2g(x) = 2. Give each answer correct to three decimal places. [1 point]

  4. (B(ii)) Write the end behavior of gg as xx decreases without bound, using limit notation. [1 point]

  5. (C(i)) Is ff invertible? Give a reason for your answer using values from the table. [1 point]

  6. (C(ii)) Is gg invertible on the set of real numbers? Give a reason for your answer using specific values of gg. [1 point]