How to Find the Length of a Chord in a Circle | Geometry, Circle Chords, Chord Length

Рет қаралды 79,630

5 жыл бұрын

How do we find the length of a chord in a circle? We go over circle chords, and how to find their length, in today's video math lesson!
Geometry sure is a blast! Today we get to go over trigonometry and sine ratios, we get to touch on right triangles, the isosceles triangle theorem, the hypotenuse leg congruence postulate for right triangles, central angles subtended by chords, and more! What a hoot!
If we have a chord of a circle with radius r, and the central angle subtended by that chord has a measure of A, then the length of the chord is 2*r*sin(A/2). We derive this formula, and go over an example of how to use it, in the video lesson. By understanding where it comes from, it is easy to recall!
I hope you find this video helpful, and be sure to ask any questions down in the comments!
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The outro music is by a favorite musician of mine named Vallow, who, upon my request, kindly gave me permission to use his music in my outros. I usually put my own music in the outros, but I love Vallow's music, and wanted to share it with those of you watching. Please check out all of his wonderful work.
Vallow Bandcamp: vallow.bandcamp.com/
Vallow Spotify: open.spotify.com/artist/0fRtu...
Vallow SoundCloud: / benwatts-3
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+WRATH OF MATH+
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Пікірлер: 84

@abhisheksinghmajhilia7078 2 жыл бұрын

Thank you! Your video is very helpful. Please make more videos on Alligation and Mixtures.

@StennettaFleming 2 ай бұрын

Thanks for the lesson .

@chazy7729 5 жыл бұрын

Thanks for the video. Amazing video as always. :)

@WrathofMath 5 жыл бұрын

You're welcome! And thank you :)

@Trident_Euclid 2 жыл бұрын

Thank you so much. This will help me alot in the machine shop.

@WrathofMath 2 жыл бұрын

That's awesome, glad to help!

@hajjex_9086 3 жыл бұрын

You life saver Thanks for this epic lesson. Your a legend

@WrathofMath 3 жыл бұрын

So glad it helped! You’re welcome and thanks a lot for watching!

@Jokerboy152 2 жыл бұрын

Thank you so much brother... Really informative

@WrathofMath 2 жыл бұрын

My pleasure, thanks for watching and let me know if you ever have any questions!

@rajkumarrajkumar-wo1zo Жыл бұрын

Thank you so much

@internationalgolfconstruction 2 жыл бұрын

Do you have any educational videos that walk us through the steps that Hipparchus used to make chord tables? I’m guessing that a series of videos walking us through how trigonometry was developed from the pyramids to Taylor series would be phenomenal.

@JosephElfassi 2 жыл бұрын

Great stuff!

@WrathofMath 2 жыл бұрын

Thanks Joseph! Let me know if you ever have any video requests!

@The_Real_MSJ 2 жыл бұрын

Thanks Man U saved my exam , god bless you

@WrathofMath 2 жыл бұрын

Glad to help, thanks for watching!

@jhngamingytph1079 2 жыл бұрын

This video help me to answer my test and homework thanks for uploading it

@WrathofMath 2 жыл бұрын

Glad it helped, thanks for watching!

@nerdlover Жыл бұрын

You are indeed a good teacher

@WrathofMath Жыл бұрын

Thank you!

@joewest1972 2 жыл бұрын

I have a circle with a circumference of 46 inches. I think finding the diameter means divide 46 by pi (3.14) or 14.64 divided by 2 equals a radius of 7.325. Now stand the circle up and picture measuring up 3 inches from bottom dead center of the circle, now draw a chord at that point parallel to the diameter. How long is that chord?

@kickboxing3728 3 жыл бұрын

Haha I had two math videos open and both of them (yours and one other) included bird sounds in the background!

@WrathofMath 3 жыл бұрын

That's a funny coincidence! Thank you for watching! If you watch some of my new lessons, they have real bird sounds because they're out in the woods! kzfaq.info/get/bejne/gaenZNuQ08ipgoU.html Or if you like spookier ambience, my Halloween lessons have some of that: kzfaq.info/get/bejne/aK2VpK6H1t20lpc.html

@sattwikbiswas4063 Жыл бұрын

I am from India. Thank you so much sir for this video. My entire concept has been cleared. I have a question for you sir. Suppose in an isosceles triangle if we draw median from any vertex on its opposite side does the median bisect the angle from whose vertex it has been drawn?

@machinedoctor3917 3 жыл бұрын

Thanx amazing

@WrathofMath 3 жыл бұрын

Thank you for watching!

@kalsept 2 ай бұрын

banger even after 5 years tnx

@WrathofMath 2 ай бұрын

Glad to help!

@yotypical_girl Ай бұрын

yeah

@anthonycasarella2000 4 жыл бұрын

Thanks

@WrathofMath 4 жыл бұрын

Thank you for watching! Let me know if you ever have any requests!

@joshuatobi2109 Жыл бұрын

Well explained

@WrathofMath Жыл бұрын

Thank you!

@simpleman283 2 жыл бұрын

I learned how to do this w/law of cosines, but this sin rule is awesome.

@WrathofMath 2 жыл бұрын

Thanks for watching! The sine rule is a real treat!

@manicmath3557 2 жыл бұрын

Do you use ipad or pc. Wat programme do u use. I wanna try my own cideos and your rpgramme seems perfecr. Could yoy tell me. Thank you

@fjejejjrbskjwjw163 8 ай бұрын

THANKS YOU

@WrathofMath 8 ай бұрын

YOU'RE WELCOME!

@richardrutebeka6109 6 ай бұрын

Thanks for the good information🙏🙏🙏🙏🙏

@lasithaaththanayake Жыл бұрын

Thank you

@WrathofMath Жыл бұрын

My pleasure!

@amealiarichards3471 7 ай бұрын

@@WrathofMath hey I got 11.47cm on my end would it still be correct ?

@ThatOneRo0ky Ай бұрын

thank you so much my math teacher never really talked about this in class and it is on the test tomorrow now i’m confident

@dorcasnhyira4593 3 жыл бұрын

You are too much😘. God bless you

@WrathofMath 3 жыл бұрын

Thank you for watching! If you're in the mood for some tunes, check out my new math song that came out today! 😊 kzfaq.info/get/bejne/ZrWiopVpvdHekps.html

@brd8764 3 жыл бұрын

A chord is a finite line segment. It is a measurable length of line.

@johnyeomans7262 2 жыл бұрын

Is there any way to find the chord length without knowing the angle and only knowing the radius? Please help - I need this for my maths assignment

@WrathofMath 2 жыл бұрын

Thanks for watching, I am not sure what you mean! Certainly if we ONLY know the radius, we cannot know the length of the chord because we would know nothing at all about the chord, aside from it residing in a circle of radius r. For example, in a circle of radius 1/2, a chord could be as big as 1 (if it was a diameter) or any number less than that.

@ryanmalapit1516 4 жыл бұрын

What if the only given is the radius how could you solve the teta ø?

@Emerson_Beau 11 ай бұрын

Assume it's 90

@nangulaitengula 2 жыл бұрын

To find the chord length will we always use sin? Or is it in accordance to angle give, For example we where given the angle at the chord

@mihirmalladi8494 Жыл бұрын

You don't have to use sin to find the chord length. I used cos and got the solution of: 2 sqrt((r^2) - ((r cos(theta/2))^2))

@buddho1135 4 жыл бұрын

Sad as these great videos go unseen by the bulk of KZfaq audience are maximum are looking for pole dancers

@tshidisopretty3275 2 жыл бұрын

How did you manage to find "70°" ??

@craigwilson8255 3 ай бұрын

It was an example, so he gave a random radius and angle. I'm not sure how to find it if we don't already have one of the angles, or "x"? Hope you got it figured out by now though lol.

@gifworld4256 5 жыл бұрын

Hey

@kkww5034 2 жыл бұрын

Why did you assume theta is 70 °

@ahmedmiraan4682 3 жыл бұрын

isn't X half the chord length because we basically bisected the triangle to make it a right angled triangle ?

@tristanpatterson8375 4 жыл бұрын

this should be 3 min long

@WrathofMath 4 жыл бұрын

kzfaq.info/get/bejne/pZt0nbFky-DNnWg.html

@gifworld4256 5 жыл бұрын

Remember me! It's been a long time!

@chazy7729 5 жыл бұрын

He is a best teacher. :)

@WrathofMath 5 жыл бұрын

Yes of course! Days go by quickly for me, it doesn't seem long at all! Did you see my response to your request for a lesson on area? I just wanted a few more details on what you're looking for. Let me paste my response here, for your convenience. I said... Sure! What kind of lesson are you thinking? Do you want to know how to find the area of a specific shape, or do you have something else in mind?

@abdulnaffay3652 2 жыл бұрын

I’m getting 10.44 for the actual answer how is it 11.18

@WrathofMath 2 жыл бұрын

Thanks for watching! I'm not sure how you're getting 10.44. The answer is not 11.18, it is 11.48. You could double check your calculator is using degrees, though using radians would not give you 10.44 either.

@richardowens6843 3 жыл бұрын

Why not use law of cosines?

@shantanudingole5155 4 ай бұрын

How to solve when theta is not given

@kalsept 2 ай бұрын

w guy

@shahadattalukder9226 3 жыл бұрын

the background birds sound is annoying . I hate to say, however I like natural birds sound

@WrathofMath 3 жыл бұрын

Sorry to hear you found it annoying! The vast majority of my lessons have no background noise, but on occasion I include some for seasonal lessons and the like. Let me know if you ever have any questions!

@elimartin5105 3 жыл бұрын

Never seen someone say so much uses stuff in my life

@GodJesusChristlovesyou_knows_u 6 ай бұрын

Brothers and Sisters, God loves us so much that He sent His Son Jesus Christ for us to save us from our sins, and he bled and died on a cross for us to redeem us from death, and to gain life everlasting, for those who put their trust in him. And what's more, he has risen, and is willing to call you to repentance (correction) and as his witness, by his grace indeed. "For it is by grace you are saved, through faith". Jesus loves you, God cares for you! Therefore, repent and believe the gospel.

@Studiesfortopper 5 ай бұрын

Amen !!! I receive it Jesus Name

@Studiesfortopper 5 ай бұрын

Every one , spread the gospel before it is too late

@Studiesfortopper 5 ай бұрын

GOD Bless All❣️

@JesusChristlovesyou_friend 5 ай бұрын

@@Studiesfortopper ❤❤

@ammarsaada9923 4 ай бұрын

That’s a lie