SAT QUADRATIC FUNCTIONS APPLICATION

C is a point on the portion of the graph of f(x) = 6x-x^2 in the 1st quadrant. If points A and B are the points of intersection of the graph of f with the x-axis, what is the greatest possible area of ΔACB?


Answer: 27



Questions:
 1) Do you think the College Board would provide the graph? Would you provide it or would you expect this from the student?

 2) Can you find examples like this in an Alg or Precalc text? Do students need more exposure to applied problems like these?

3) How would you rate the difficulty level of this question --- 3 is medium, 5 is hard.

4) EXTENSION
Change to f(x) = kx-x^2

Ans: k^3/8
Note: College Board is moving toward use of parameters. Can you guess why?



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