Result of the Day 1 Challenge of my May 2021 Math trigonometry mini-contest for D.Buzz 😎

in STEMGeeks2 months ago


Manuel found that cos (2θ) = -7 and θ is not in the first quadrant. To remember it more easily, he wants to convert cos (2θ) into sin (θ). What is the value of sin (θ)?

(original post at 👈)


no solution 🎯


There is no angle which when inserted to a cosine function outputs a value of -7. It is because there is no triangle where one of the sides is 7 units while the hypotenuse is only 1 unit (from the identity cos (θ) = adjacent / hypotenuse), since the hypotenuse must be longer than both the legs of the right triangle.


(Sorry for the gritty graphics of my image made using Microsoft Paint) 😅

Winner: @minus-pi 🏅

1 HIVE has been sent to @minus-pi's Hive account. 💰

Nobody else has tried to submit their answer for the problem. 😮

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awesome, thanks @savvyplayer! :)
Let's hope there's more participation in the following days.

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Sorry for the late results! 😁 I usually have time only for short comments on Hive nowadays. 😅

no need to apologise 😅

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Honestly, I just post Math problems which I hurriedly think would have answers, because I don't want to spend too much time devising a problem that would also take a lot of time for me to type the solution. 🙂

they're good! I know it's hard to come up with questions that have the right mix of complexity vs. the time it takes to solve them yourself :)

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Thanks for understanding! 😀

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