The following, courtesy of commenter Jay, is from Jacaranda’s Mathematical Methods 34 text.
We have been hammering this idiocy for a baker’s decade. At this stage there is no excuse, if there ever was.
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The following, courtesy of commenter Jay, is from Jacaranda’s Mathematical Methods 34 text.
We have been hammering this idiocy for a baker’s decade. At this stage there is no excuse, if there ever was.
In our country, this crap was introduced 4 years ago. There must be a well of idiocy where this is springing from. What is particularly idiotic is that this nonsense is advocated by real-life-problems-fetishists, given that
and 
almost never have the same units, so intersecting them makes no sense at all. Which is why it fits perfectly into the curriculum.
Counting the years, . . .
Franz
In Germany do they also fake the method of solving?
I think any real-life use case would fall into 1 of 2 categories:
1. You’re finding the point where x=y, which definitely doesn’t require the inverse, nor does it require knowing anything about inverse functions
2. You’re finding the point where the function and it’s inverse intercept, in which case knowing Jacaranda’s method is counter-productive
Either way, Jacaranda’s method isn’t gonna help you with any real life problems
I think we had better review the meaning of “real life”.
Is this a symptom of VCAA examiners’ reports, perhaps? If so, we can be a bit more forgiving of the textbook author(s) trying to be relevant.
But only a bit.
To hell with that. The statement is plain wrong. Either the authors don’t care that it’s wrong or they haven’t listened to a damn thing for the last decade. Either way, screw them.
No argument from me. Just a pondering of the history/sequence of events.
Based on this idea of functions having a so-called “three-way point of intersection” I propose that functions like f(x) = x^3 should be called “randy” and functions like g(x) = 1/x should be called “prudish”. Then one could ask questions like: “Let f(x) = ax^3. For which values of a is f randy”?
SRK, you have a Renaissance mind, as Les Patterson once said.
What about
which only intersects 
once but intersects its inverse three times, the intersections just happen to all be on the line 
..?