Sat trying to confuse people?

Test Preparation
1

<p>If the function ƒ is defined by ƒ(x) =(x-a)(x-b)/(x-c) , where 0 < a < b < c, for which of the following values of x is ƒ undefined?</p>

<p>I a
II b
III c </p>

<p>None</p>

<p>I only</p>

<p>III only</p>

<p>I and II only</p>

<p>I, II, and III</p>

<p>The answer is III only. It's pretty easy because you just see that x-c is on the bottom and thats the only place it can be undefined.</p>

<p>I got that answer easily</p>

<p>However, for those who don't understand, they're given this explanation:
If x = a, then = = = 0. If x = b, then = = = 0. If x = c, then = = , which is not defined because division by 0 is undefined. Therefore, of the three values, a, b, and c, the only one for which ƒ is undefined is c.</p>

<p>Difficulty: Medium </p>

<p>Oh, well you can't see the equations they have but they're just long and unecessary for this problem. I could imagine this explanation confusing to a math deficient. They could just say c is on the bottom, so its the only one that could be undefined.</p>

<p>Ok, just getting it out there.</p>

2

<p>I think it's easier and more concise to say:
Since the denominator is c-c=0, the number can not be divided. Therefore, it's undefined.</p>

<p>I agree, the CB's explanation to things aren't the best ever. Especially sentence completion ones. They just insert the word in to the sentence, and say that it's logical.</p>

3

<p>Yeah I agree too, once they made a pretty simple paint can problem (probabilities) soo complicated, i had to scroll down like 5 times reading thru the entire explanation</p>

<p>i hate the sat man, it just sucks, all around, they cant give a good test or good answers</p>

4

<p>Yeah that question, which i think was a day or two ago, is rediculously ambiguous. The explaination still didn't make sense to me, what is x supposed to be?, i just be C, like said above, b/c if it was 0 it would be undefined</p>

5

<p>I just got c=0</p>

<p>I didn't get it wrong, so I didn't see the reason behind it. The question isn't ambiguous though.</p>