Sigh. We really hate updating WitCHes.* We have about a hundred of these things to do, and we’re generally thinking of the updating as a task for retirement or, better, for a reincarnation. However these NHT WitCHes, and this one in particular, have highlighted a degree of confusion. So, alas, it seems worthwhile sorting out the issues while the issues are in mind.
“All students were awarded [the] mark for this question.”
Yep, the question is plain stuffed. We think, however, there is more here than the simple wrongness, which is why we’ve made it a WitCH rather than a PoSWW. Happy hunting.
UPDATE (11/05) Steve C’s comment below has inspired an addition:
The third greatest issue with the exam question is that it is wrong: none of the available answers is correct. The second greatest issue is that the wrongness is obvious: if lies in a sector then the natural guess is that will lie in one of three equally spaced sectors of a third the width, so God knows why the alarm bells weren’t ringing. The greatest issue is that VCAA didn’t have the guts or the basic integrity to fess up: not a single word of responsibility or remorse. Assholes.
Those are the elephants stomping through the room but, as commenters as have noted, there is plenty more awfulness in this question:
“Letting” is sloppy, confusing and pointless;
The term “quadrant” is undefined;
The use of “principal” is unnecessary;
“argument” is better thought as the measure of an angle not the angle itself;
Given is a single complex number, “the complete set of values for Arg()” will consist of a single number.