Timeline for How to layout a solution to a trig equation?
Current License: CC BY-SA 4.0
6 events
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| Aug 27, 2020 at 7:03 | history | edited | Dave L Renfro | CC BY-SA 4.0 |
In two places I'd written "are integer multiples of $2n\pi$ added to the above", which although is technically correct, is unnecessarily convoluted.
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| Aug 26, 2020 at 19:12 | comment | added | Dave L Renfro | I used the ellipses to more strongly indicate truncation, and the purpose of giving a few digits like this was so that students could later check the calculations. In written handouts I did typically use the $\approx$ symbol, but on the blackboard I usually didn't because sometimes students don't notice it or don't reproduce it in their notes. One of the problems with using implies between the steps is that it's often not just "Step 6" implies "Step 7", but something like "(part of hypothesis) + (Step 1) + (Step 3) + (Step 6)" implies "Step 7". It also adds clutter at this level. | |
| Aug 26, 2020 at 19:02 | comment | added | Xander Henderson♦ | Oh, and I would use $\approx$ rather than $=$, and ditch the ellipses, but that's a pretty minor point. I really am just nitpicking, now. | |
| Aug 26, 2020 at 19:01 | comment | added | Xander Henderson♦ | (+1) My only comment is that I really dislike it when students write things like $$ \sin(\theta) = x \\ \theta = \arcsin(x) + \text{whatever}. $$ I strongly feel that there should be a "verb" which links those two lines together, e.g. $$ \sin(\theta) = x \\ \implies \theta = \arcsin(x) + \text{whatever}. $$ I also worry about numerically checking for extraneous solutions, but graphing software can give one a better sense of how the problem is working. | |
| Aug 26, 2020 at 18:34 | comment | added | Dave L Renfro | maybe this would be how I'd want students to present their work --- To be more accurate, this is how I might present the solution in class or in a handout. I wouldn't expect students to include as many words, but their solutions should still be sufficiently complete that (in my opinion) a good student in someone else's trig class could follow their reasoning. It should also be sufficiently complete that if they make a minor error along the way, I can still continue reading along with them for the purpose of awarding points for other aspects (i.e. award appropriate partial credit). | |
| Aug 26, 2020 at 18:22 | history | answered | Dave L Renfro | CC BY-SA 4.0 |