Zarrolou wrote:
How many values can the integer p=|x+3|-|x-3| assume?
A)0
B)7
C)13
D)14
E)Cannot be determined
My own question, as always any feedback is appreciated
A)0
B)7
C)13
D)14
E)Cannot be determined
My own question, as always any feedback is appreciated
Dear Zarrolou,
Here's some feedback. I like the question itself quite a bit. My only criticism are the answer choices. Obviously, the OA (C) need to be on the list, and (B) 7 is an excellent distractor (what folks get if they just plug in integer values of x). I don't know about (D) 14 --- who would pick that? If folks realize that the output is +6 for x > 3 and -6 for x < -3, I could see them saying, "Hmm, how many integers from -6 to 6? That must be 12." Forgetting inclusive counting in something like this --- that's a huge predictable error. I think both 6 & 12 would be good to have on the answer list for this reason. I have no idea how anyone could possibly pick (A) 0 ---- anyone who can plug in any single number and get an output will know there are now zero outputs. I see that as a wasted incorrect answer: one that no one will pick. Choice (E) is debatable. I would recommend 3, 6, 7, 12, 13 as the answer choices myself.
What do you think?
Mike
