Timeline for How to explain this trigonometric problem properly?
Current License: CC BY-SA 3.0
8 events
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| Nov 12, 2016 at 19:08 | comment | added | Simply Beautiful Art | @danielhast for the same reason the OP avoids the unit circle, you'd end up having to remember how to construct those triangles, and as far as remembering goes, my answer is arguably simplest. | |
| Nov 12, 2016 at 19:01 | comment | added | Daniel Hast | If you understand the reasoning behind those special values, tricks to memorize them shouldn't be necessary. Sine and cosine of $\pi/4$ come from an isosceles right triangle; sine and cosine of $\pi/3$ and $\pi/6$ come from half an equilateral triangle. The Pythagorean theorem gives the side lengths in both cases, no tricks required. | |
| Nov 12, 2016 at 16:42 | comment | added | Simply Beautiful Art | @DanielHast Well, clearly by the time one gets to this, they should have a basic understanding of why cosine and sine have those special values. This answer doesn't serve to teach trigonometry, just to help others recall certain values more easily. Your answer does a wonderful job of that, and I applaud, but the OP still isn't satisfied. | |
| Nov 12, 2016 at 16:35 | comment | added | Daniel Hast | Why it does help to memorize those values? What's the point if you don't understand why cosine and sine have those special values? | |
| Nov 12, 2016 at 16:27 | comment | added | Simply Beautiful Art | @DanielHast Well, after learning what sine and cosine mean, it helps to memorize these values since they appear more than other values. And as to how much of an exercise this is, I think it's really easy. If you take a look, there is a pretty simple pattern, one that takes only moments to memorize. | |
| Nov 12, 2016 at 16:06 | comment | added | Daniel Hast | Why would you ask students to memorize values of cosine or sine? It seems like a pointless exercise that short-circuits the actual (and actually interesting) geometric reasoning that goes into finding those values. | |
| Nov 12, 2016 at 14:03 | history | edited | Simply Beautiful Art | CC BY-SA 3.0 |
added 1 character in body
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| Nov 12, 2016 at 13:54 | history | answered | Simply Beautiful Art | CC BY-SA 3.0 |