Tonight my 15-year-old explained the concept of "reference angle" to me. Is that the approved way to teach trigonometry these days?
-
-
Replying to @stevenstrogatz
The approved way to teach trigonometry these days is plainly inferior to Ptolemy's. The masters generally know best: http://bit.ly/2hsqcWl
2 replies 0 retweets 0 likes -
Replying to @MathPrinceps @stevenstrogatz
Beautiful, but Ptolemy doesn't use diameter = 1 as the authors claim. Rather he uses r = 60 = sexagesimal 10. More like unit r than unit d.
2 replies 0 retweets 1 like
Replying to @viktorblasjo @stevenstrogatz
Agreed, of course. But these points seem to me pedagogically inessential. What matters is that Ptolemy had no trouble with obtuse angles.
1:24 AM - 26 Sep 2017
0 replies
0 retweets
0 likes
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.