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Surprises me when people hate on trigonometry. I enjoyed trig in high school so much that I made it my internet alias.
by Sohcahtoa82 1y ago
Surprises me when people hate on trigonometry. I enjoyed trig in high school so much that I made it my internet alias.
- cratermoon 1y agoI find it conceptually cool, but I struggled in school with learning the identities, memorization being one of my weak areas.
- Sohcahtoa82 1y agoIf you know your trig well enough, you can derive the identities. For example, knowing that cosine and sine are the exact same wave, just 90 degrees out of phase, it's trivial to know that sin(angle) = cos(angle + 90) cos(a)^2 + sin(a)^2 = 1 is easy to show, too. If you use a=0, it's trivial. But try using 45 degrees. It turns into (sqrt(2)/2)^2 + (sqrt(2)/2)^2 which simplifies to 0.5 + 0.5 = 1. Many of the others can be derived by just manipulating the Law of Sines or Law of Cosines. Fun fact: The Pythagorean Theorem is actually just a special case of the Law of Cosines: c^2 = a^2 + b^2 - 2*a*b*cos(C) Recall that in the Law of Cosines as I've written it, the lowercase letters are the sides, and the large C is the angle opposite that side. So if you choose your hypotenuse to be c, then the opposite angle, C, is 90 degrees. cos(90) is 0, so that whole last term gets cancelled out and you're left with the equation known as the Pythagorean Theorem. I really wasn't kidding when I said I enjoyed trig.
- Sohcahtoa82 1y agoToo late to edit now, but wanted to add a note: Knowing that cos(45) == sqrt(2)/2 seems like something you would need to memorize, but if you just draw an isosceles right triangle with sides equal to 1 and use the Pythagorean Theorem you'll find that the hypotenuse is sqrt(2)/2.
- untilted 1y agoObligatory xkcd: https://xkcd.com/809/ https://xkcd.com/809/
- rmonvfer 1y agoThis made my day. Great alias!
- Waterluvian 1y agoDid you learn it as “sign on highway, cozy at home, tan on arm”? That’s basically the only high school math that stuck with me. Oh and I guess negative b plus or minus b squared something something four a c over two a. I think there’s a square root to shove most of that into.
- cameronh90 1y agoI always thought sohcahtoa itself was quite memorable. Sounds like a war cry!
- bombcar 1y agoOr something those wordy math textbooks would have had - the Sohcahtoa Indians who dealt in triangles …
- jihadjihad 1y agoIt sounded to me like something some colonists would carve into a fence, like CROATOAN. SOHCAHTOA.
- jcalvinowens 1y agoIt would get him fired today... but my trig teacher showed up to this lesson shirtless in a floor length native American headdress, and ran into class yelling "I am Chief SohCahToa! Never forget my name!!". And by God, I never have. Thanks Mr. Wilkinson.
- philipallstar 1y agoThat sounds like an actual teacher! Amazing.
- m463 1y agoalways made me think of krakatoa (the exploding island)
- rndmio 1y agoIn the UK it was “Attack Henry Cooper, outside his shop, on a Tuesday” no idea why the random violence but I never forgot it
- chris_wot 1y agoYou think they hate trigonometry, then you tell them about radians and they really hate trigonometry. Which is... crazy really.
- memset 1y agoSome Old Horse Caught Another Horse Taking Oats Away