This one is a combo WitCH. The main concern is a multiple choice question from last week’s Methods Exam 2. The question may not be an “error” in the newspaper sense, but it is bad. To appreciate some (but far from all) of its badness, however, we need to see VCAA’s solution. We won’t likely see that solution, however however, for months, if ever; transparency is not VCAA’s strong suit (Section 7).
To deal with this, we’ve teamed up last week’s MCQ with a similar MCQ from the 2021 Exam 2, together with VCAA’s solution to that earlier question from the exam report. Last week’s question appears first.
Some clarifying remarks.
First of all, I am guessing the majority of students and teachers (and 99.9% of the general public) who read this blog have no proper understanding of the mathematical issues. If only for this reason, it’s not gonna make it into the Herald Sun. But, trust me, it’s bad. It’s the kind of thing that makes mathematicians start blogs.
Thirdly, the underlying material is all explained well enough, but at a superficial level, in a reasonable first year uni subject. Because the explanation is superficial, however, the ideas don’t stick well and people forget. (Few teachers do, or at least do well enough, the solid second year subject in “real analysis” you need to really get this stuff.)
It is perhaps reasonable to include this material in VCE, even if there’s no compelling reason to do so. If it is to be included, however, the syllabus and textbooks and exams have to be written and vetted by people who understand it. That ain’t happening.
This stuff is gonna drive me nuts, I know. I will try to kill it one more time, with a proper update soon.
For now, let me just make clear what a student should do in practice with an MCQ like the above: autopilot. Just match the function values, match the derivative values and do whatever the two resulting equations suggest that you do. That’s all there is.