What does sine actually mean?

The etymology of sine is fascinating.

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[UtubeWatchu]

That's a cool fact. Etymology is amazing.

[adityasingh]

In Indian astronomy, the study of trigonometric functions flourished in the Gupta period, especially due to Aryabhata (sixth century CE), who discovered the sine function. The first actual appearance of the sine of an angel appears in the work of the Hindus. Aryabhata, in about 500, gave tables of half chords which now really are sine tables and used jya for our sin.

[YoungGandalf]

Math, History, and English class in the same video!

[desmondlau]

After you posted the visualisation video the other day, it hits me on this exact question! This video just came at the right time!

[M_ht.]

In today's Indian high school mathematics books, we still have the word 'jya' but it means chord of a circle now

[joshuarosen]

I had often wondered. I have to say that I thought the explanation would be simpler and more sensible but thank you for that interesting and informative video.

[huzefa]

I like how you make videos dedicating to indians as well 😊
This is what math history is 😀
Btw i am in Kuwait ( Arabic country ) but i am indian studying in indian school... so i know both the languages you showed 😅

[Anas_Sherif]

In Arabic we still say Ja as sine and Jata as cosine

[kilroy]

It's still called "sinus" in various languages.

[lawrencejelsma]

... and this is reporter for Mind Your decisions ... "sin" ing off! 🎤🤓👍

[FundamSrijan]

I still remember that this is written in class 10th maths book ( chapter 8 I guess )

[MixbOOsted]

i think almost half of his audience is from India ;) ??

[darylewalker]

What did “kojya” literally mean?
In English, “cosine” stands for the complementary sine, what did the “ko” part mean back then?

[ScienceNectar]

Also utkramajya for tangent and it is kotijya for cosine

[SANATAN_HI_SATYA_DHARMA_HAI]

The radius is called Trijya which means the one born of three jya, when u dont know the centre of circle u need three lines (chords - jya) to find the centre and from there u can know the radius- Tri-jya

[maximilian]

But how did the ancient greeks know about it then? Didn't they use it to calculate the circumference of the earth?

[adritobiswas]

Even in bengali language (derived from sanskrit) the chord is called jya,

[issamzreik]

Thank you for your content
But I have a question:
When I saw these identities:
co sine(x)=sine(90-x)
co tangent(x)=tangent(90-x)
co secant(x)=secant(90-x)
I expected that the (co) is the first two letters of the word (complementary angle)
So is this correct?
I saw this in wikipedia so if someone who knows that this is wrong and he has sources, then please edit this wikipedia page
Sorry for my bad English I am not native

[agrajyadav]

Indian science was the most precious in ancient times. Hope indian science can be great again.

[davidseed]

isle and island i think have different roots. a sort conveegent evolution.
perhaps it was deliberate to bring together the ideas of bowstring and bendy which are both relevant to the sine function