The task is: Given a triangle with q identical lines, in this way as you can see on the picture. The orange lines are the same. Calculate γ!
ΔABC′ is an isosceles triangle, therefore β1=γ.
The sum of the angles at the B point is 180∘, because AH is a line:
180∘−2γ+β2=180∘β2=2γ
From the isosceles triangles and the sum of angles at the C point:
β1+180∘−2β2+β3=180∘⟹β3=4γ−γ=3γ
Same way β4=4γ,β5=5γ,⋯,βn=nγ, because if we see an angle:
βn−2+180∘−2βn−1+βn=180∘⟹βn=2βn−1−βn−2=(2(n−1)−n+2)γ=nγ
This is true for the first, second and third angles, so this must be true for every angles.
If we have a triangle with q lines, then the last β is the 2q−3th.
Now in the bottom HG′H′ triangle: α+α+α+β6+β6=180∘ or generally 3α+2β2q−3=180∘. But if we see the big triangle 2α+2β2q−3+γ=180∘. Therefore α=γ. After substituting: 3γ+2β2q−3=180∘. Replacing β2q−3:
3γ+22q−3γ=180∘3γ+qγ−3γ=180∘qγ=180∘γ=q180∘
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Comments
Nice proof! Explains where I went wrong! @Páll Márton.
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Thank you! Did you solve my problem?
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No! That's why I said it explains where I went wrong.
Angles, not angels.
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Yeah. I use Word2016 to write the text and I just paste them there, but the default language isn't English so the autocorrector "corrects" my "typos".
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I will add this word to the Word. Last time it wrote mooves instead of moves
Oh. I see. Doesn't happen with me though.
Also, tip:
If you wish to delete a problem, copy and paste the solution in Word, then copy the problem, go to create a new problem (open a new tab for this), paste the original problem's text, copy the title, paste it in the title section, change the answers (if needed) - if not, press Post. Then, copy the solution from Word, paste it and make any corrections (if needed) - if not, press Preview and Submit. Then close the Word Document.
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I used this technique for my Hexadecimal Equations Problem 6 up to Version 4.
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this note isn't very famous I think you can continue this :)
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Also, what if (for your next problem involving this):
3600180=0.05 degrees
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3600 identical lines?
Triangle withLog in to reply
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3601 identical lines?
Triangle with3601180=0.049986115 degrees
Also, how do you do the degree sign? Baffles me...
P.S. Check out my note - Interesting Thing about Multiplication Last Digit Sequences (Even)
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3601 identical lines?
What about the triangle withLog in to reply
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Excellent exposition.
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Thank you!
Wow! Good proof!
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Thank you!
Excellent Proof @Páll Márton.
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Thank you!