How to draw regular polygons inscribed in circles - Compilation

In this video, I have compilated with some methods to draw regular polygons inscribed in circles, starting with the general method to draw regular polygons of any number of sides, and continuing by the particular methods to draw an equilateral triangle (8:59), a square (11:00), a pentagon (13:08), a hexagon (18:40), a heptagon (21:46), an octagon (25:56), a nonagon (29:52), a decagon (35:30) and a dodecagon (41:48).
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This KZbin channel is dedicated to teaching people how to improve their technical drawing skills. It focusses on drawing figures from the geometric plane to descriptive geometry and also different systems of technical drawing representation.
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Dubbed by Frank Shaw.
Music by Antonio Fernández Ruiz. antoniofernande...
#Geometry #HowtoDraw

[@calvinjackson8110]

Even though I know a true regular heptagon is not constructable in the classic sense this approximation is so impressive. Your eyes tell you it is a real regular heptagon, but my mind knows it cannot be exact. It's still impressive.

[@trueleyes]

I loved geometry as a kid and it has been a long time since I have used any trig but as of late I found myself in need of doing some trig to solve some building designs I was facing and it was great to play with numbers again. For a long time, I have used other methods of constructing multi-sided buildings and furniture using math and other techniques known to carpenters but these mentioned you have shown here are really quick and easy to learn. Thank You for the time and lessons they will be used by me for sure. I have subscribed.

[@grahampalmer9337]

My Maths teacher at high school was a a droning Scot who's only use was as a cure for insomnia. :-/ Consequently I learned next to nothing, which forever blighted my career in Aerospace. I picked up some basic competence late as required. I now need to make a bespoke tool for removing a part on my Ovlov - which I won't buy from 'them' for £75! If I can transcribe your method (I only need the 'point 2' dimension really) I can modify my £2 plumbing part to do the job. Many thanks for your instruction.

[@Khether0001]

that is just FANTASTIC!!! thank you so much for this explanation!!!!!! :) it was EXACTLY what I was looking for, I imagined that using the diagonal line to project the division in parallels onto the circle could be the way you would do that, but I had no clue how to actually do it! this is beyond awesome!!! thank you again!!!

[@MuhammadArfanSyafriArt99]

Terima kasih sudah berbagi dengan kami... akhirnya aku menemukan teknik ini Thanks a lot🙏👍

[@willbagthegreat]

In the decagon construction, once you have the pentagon drawn, AF is already the perpendicular bisector of side EG, so you can just set the compass to length EF for the side length of the decagon.

[@charlie03c]

Your videos are outstanding, I draw a lot of optical art by hand and you have helped me understand shapes better.

[@lefthandstory1280]

Beautiful sharing friend😃✌️.....

[@KevinKurzsartdisplay]

I’m gonna use those techniques for my artwork.

[@nagendrachandu3024]

Seeing it 1 day b4 architectural drawing exam and it's very helpful 👍

[@calvinjackson8110]

The polygons are done so cleanly and so very neat and so precise like, even though they are still not perfect. The program you are using is very impressive. Can it make lines even thinner?

[@ez2000co]

This reminds me my secundary school "Technical Draw" course. We used the Bronislao Yurksas text book. Mid 80's.

[@adhithyansaji4248]

It helped me in my assignment thanks a lot

[@enlikeenamul7102]

13:28 Pentagon 18:56 Hexagon

[@ЛюдмилаЯловченко-ж7ю]

О! Геометрия, ты вечна ---гордись прекрасная собой .

[@cuteyes02]

22:00 - It has been proved by Gauss that a regular haptagon cannot be made by compass-and-straightedge, because 7 is not a Fermat Number. The way you draw a haptagon is firstly found by Albrecht Dürer, which has 0.2% error.

[@bowlineobama]

Thanks so much for sharing this skill.

[@irenejuevesano1792]

Tnx for this vedio dude😉😃😃😊😊This vedio help me to know and study this polygons because this is our lesson.

[@bogdanrusu]

In the first construction where you use the division of the vertical diameter into 10 equal parts, the obtained decagon is not regular because the sides that start from point P are not equal to the others, they have a shorter length

[@GiantSnipe]

This is great - all comes flooding back. Does anyone have a good tip for not leaving a hole in the paper from the compasses? Thought of using a bit of card under it, but how to stop it moving and not leave a mark?

[@pdias8469]

Thanks. I am very happy.

[@CDAHER100]

Excelente didática.

[@alaaalbudeiri1064]

Thank you very much teacher

[@РаушанБарлыбаева-о1у]

Хороший транспортир с треугольником и параллельными линиями.

[@manuelpanganoron4529]

I was excited to learn that you have a method for making a heptagon... but when I tried it in autocad there was a slight difference... I tried calculating the angle of your method and it gave me 51.31781 degrees... 2*arcsin(sqrt(3)/4)=51.31781deg ... and then compared with 360 /7=51.42857 deg it was a nice approximation though... I really thought you discovered a way to disprove mathologers claim that this is not possible using compass and straight edge... 😞

[@Selenic_c]

Tysm ❤❤❤

[@tilesetter1953]

Excuse me but in drawing the decagon from the pentagon you did not have to draw a perpendicular bisector because you already have one at the bottom of your pentagon: the original perpendicular diameter is the perpendicular bisector of side EG of the pentagon!

[@maamzenny7757]

Thank you very much, this is a great help for my lesson.

[@colrajdhan]

I learnt a much simpler way in my high school for drawing a polygon within a circle.

[@mikeeldridge637]

You should have learned that (learnt) is not a word.

[@h-Films]

@@mikeeldridge637 it is they are both acceptable spellings

[@yogeshjoshi4973]

Super video sirji

[@dansarbescu556]

For the decagon: once we have the vertices of the pentagon we find their symmetrical points with respect to the center of the circle.

[@ahmedabdulkerimyusuf9511]

How can you divide a semi circle into a number of equal arcs?

[@TheRojo387]

So there it is. The true "Gearsmith's Friend" is the humble compass!

[@jabulism]

thank you, what is the pcd of the five hole flange?

[@apurvaalim7805]

Thanks sir I really need this Thanku so much🥰

[@arshithalarish9334]

Nice one 😊

[@sthapathis.d.bhaskartemple1374]

Thank you🙏🙏🙏🙏🙏❤️

[@divineamedumankwedzi3467]

Good job

[@artistaplastico6771]

Excelente

[@blezmo]

What size is each side and what size is the radius?

[@pinview8519]

Wonder whether there is a mathematical prove for the method?

[@MrAksupriatna]

I am also looking for the video showing those kind of proofs

[@MasterOfFudge]

How do you do the parallel lines?

[@ArthurGeometry]

kzbin.info/www/bejne/eV66pmqdhLijfq8

[@ritabanik382]

You are just after our teacher in school.

[@fockoff]

decagon does not need other point than point 2 on diameter right? so why?

[@kenlee2374]

what is the reason behind the point 2?

[@abdullahimohamed1704]

What's the size of the first circles because it's the where am making the mistakes

[@ArthurGeometry]

I recomend you a radius=5cm.

[@abdullahimohamed1704]

@@ArthurGeometry ohh me iwas using 8 thank you teacher🙏🙏

[@ohangdaus3409]

I mean could you share the video. How to draw 11 side on circle with acurate.

[@calvinjackson8110]

A regular 11-gon is not constructable (11 is not a Fermat prime) using only the Euclidean tools ( an UNMARKED straight edge and a compass). Any such construction of the regular 11-gon gives an approximation like the regular heptagon that was done where a length of (1/2)sqrt(3) was used as an estimate of a side of the heptagon. The result was impressive but it is NOT AN EXACT construction.The other alternative is to bring additional tools into the construction if you want an exact regular 11-gon. I have found on the internet 2 mathematicians(I believe) as recent as 2014 discovered by using a neusis construction(meaning they used something other than the Eucllidean tools) a way to construct the exact 11-gon. In 1796 Gauss at the age of 19, discovered how to construct, with Euclidean tools only, an exact 17-gon!! The number 17 is a Fermat prime. Someone has figured out how to construct an exact 257-gon!!

[@заряд-о3д]

В какой программе это выполняется?

[@ВоваЮщак]

Самое первое построение некорректно с "условной" параллельностью таких линий, фактически проведенных "на глазок". Из правильного пятиугольника - другое дело.

[@АлександрКакушкин-л9ж]

Первое построение позволяет построить любой многоугольник со сторонами отличающимисяот сторон правильного многоугольника на пару процентов. Единственное, там все вершины надо получать проецированием, а не только первую.

[@podboq2]

i want to know who figured it out and how they figured it out: how to find 1/5th of the circumference of a circle using only a straight edge and compass.

[@calvinjackson8110]

To answer your question: The ancient Greeks over 2000 years ago knew how to construct a regular pentagon! No one knows who exactly was the first to discover how. Euclid the father of axiomatic and formal geometry was born circa 300BC. So the Greeks were dallying in geometric construction of polygons at least 2 centuries before Christ ( not to presume on your religion, if any). Who knows, someone may have discovered how to construct a regular pentagon in ancient Egypt 2500 BC!! The ancient Greeks are not the only race with minds and could think! So much knowledge has been lost and there is undoubtedly FAR MORE ancient peoples knew and discovered that would completely trash our history books today!!

[@murkdurk8961]

I never understood why people draw a circle first, instead of a line first.

[@michaelanthonyscottmacnab1781]

According to CAD the Nonagon is not exact, please comment.

[@calvinjackson8110]

A regular 9-gon has no exact construction using only the classic Euclidean tools, which are an UNMARKED straight edge and a compass. 9 is the product of two equal Fermat primes, namely 3. Gauss showed that such regular polygons are NOT constructable. For this same reason a regular 18 and 25 gon are not constructable: 18 = 2×3×3 and 25=5×5, since 5 is a Fermat prime.

[@luiginodilenardo6820]

Yu elp andestending area civile Uso lui

[@TORAH-613]

I dont understand why you only used Q and 2 and not any of the other 8 points that you marked for no reason. If Q and 2 got you B and all the other sides are equal the other 8 marks were useless

[@PASHKULI]

but why? proof?

[@jeffreycunningham4840]

Hell for those who want to believe that ❤️🥴

[@kism4t574]

Upes 💀💀💀

[@rafaelcaballosanchez1393]

GG

[@RayHanar-l8q]

11 sided polygon hendecagon

[@ArthurGeometry]

kzbin.info/www/bejne/goilpop8iLV_qsk

[@carmenpeez378]

Habla un poco en español

[@abdullahimohamed1704]

Need an answer please 🙏 a

[@h-Films]

that is not a very even heptagon

[@Diamondblade2008]

That is because 7 is not a Fermat prime.

[@h-Films]

@@Diamondblade2008 ik

[@carlkundan8178]

um i think i like it but not so much

[@jeffreycunningham4840]

But y'all ain't invited anyways.

[@surasuresh8920]

GG. is. Look. You

[@herbieherbert9964]

Help

[@abhishekchandarana6107]

U

[@ivangilepo8549]

Shown = Shaun