Finding The Day of the Week From any Date (Better Version)

Finding The Day of the Week From any Date (Better Version)

mathOgenius

1 год назад

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@mathOgenius
@mathOgenius - 27.10.2022 13:32

I hope you enjoyed !

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@fungun9653
@fungun9653 - 29.01.2024 18:42

How do you do the same for century years for example 1 january 2000? pls answer

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@702heath
@702heath - 09.12.2023 00:03

??)¿(??

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@nirvana2418
@nirvana2418 - 03.11.2023 00:17

Tuesday

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@santoshgujar5237
@santoshgujar5237 - 09.10.2023 09:28

Thank you, Sir, 🙏🌺😇

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@Unknown-iy3bs
@Unknown-iy3bs - 23.08.2023 08:05

Imagine him as a teacher 😭

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@Kumar-hp7ow
@Kumar-hp7ow - 20.08.2023 20:06

You're a Briliant guy sir

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@adrianandrei3657
@adrianandrei3657 - 14.07.2023 00:41

I realy apreciate your work,love your calming vibe! You explain very well im just stupid!

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@HonTech
@HonTech - 06.07.2023 11:58

May i know from where extra 4 odd days came?

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@Brid727
@Brid727 - 25.05.2023 11:06

I am still confused as to how 1800 is not a leap year because if 1600 was a leap year, 200 years would pass to be 1800 and 200 is divisable by 4. So, 1800 should be a leap year. May I kindly get an explanation as to how 1800 is not a leap year or was this an error in the video?

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@NalenDudez
@NalenDudez - 05.05.2023 03:26

you were born thursday

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@bradley5804
@bradley5804 - 06.04.2023 19:12

So that means march 22 2007 was a thursday

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@FocusonStudy-uj7bx
@FocusonStudy-uj7bx - 04.04.2023 08:57

Thursday

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@Ima-hoot
@Ima-hoot - 22.03.2023 12:11

There is a simpler method instead of calculating leap years and then subtracting to figure out normal years.
For every year add 1. For every leap year add extra 1 (this is equivalent to leap year having 2 extra days and normal year having 1 extra day ).

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@shubhamchaudhuri9279
@shubhamchaudhuri9279 - 17.02.2023 00:09

thursday

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@shout_graffiti2084
@shout_graffiti2084 - 30.01.2023 18:34

Will the Next renewal be 2000 and if its is how to do for single digits last number eg 2001,2002 ,2003 , .......

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@ssclover30
@ssclover30 - 29.01.2023 15:53

You make understand everything too briefly.❤️❤️

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@daviddobosz7418
@daviddobosz7418 - 22.12.2022 00:10

I am having great difficulty figuring out what you are describing because I just don't get it. Somebody help.

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@daviddobosz7418
@daviddobosz7418 - 21.12.2022 23:58

I simply do not understand all of the explaining here. Please help.

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@chanduuuuu3
@chanduuuuu3 - 21.12.2022 21:35

Great playlist! Enjoyed watching it.

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@marcyroblox_edits6657
@marcyroblox_edits6657 - 18.12.2022 00:43

I can't tell if I'm dumb, but I'm still confused lol 😓

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@user-ix1bt3ox4s
@user-ix1bt3ox4s - 09.12.2022 07:47

老師教的很好。換位思考是根本。多謝。多謝。

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@MagmaSona
@MagmaSona - 05.11.2022 00:08

Great Paryag ❤️ keep it up Brother dear.... Can you some Maths to describe space and the it's smallest Possible Value. And is space makes meaning at the smallest level and what doe it comprises of ?

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@thecalendarninja
@thecalendarninja - 04.11.2022 01:26

1.) I simply pre-memorized all 366 possible dates as a value from -3 to 3.
2.) Then I just add that to one of the 4 possible century codes of 2,0,-2, or 3 (7 possible century codes for Julian from -3 to 3) and finally,
3.) Add that to a pre-memorized value for each of the 100 years from 00 to 99.
For example, my birthdate of March 19, 1982 goes:
-2+3-3=-2 so Friday! Or shortcutting, I just cancel the 3 and -3, and -2 is Friday! The fastest way to do this is to pre-memorize all 100 year values from 00 to 99. Then I just add that to the century code and finally add that to a pre-memorized value for each of the possible 366 dates (these 3 values can be added together in any order you like). For example, June 15, 2012 would simply be:
2+2+1=5, so Friday!
June 15 always has a value of 2 (pre-memorized)
2000's has a century code of 2
and,
year 12 always has a value of 1 (pre-memorized)
2+2+1=5, Friday!
Anytime leapyear happens just subtract one from the answer for January or February only, all other months stay the same!
I calculate any day of the week using my method in less than a second, almost instantly to 2 seconds tops if I'm thinking a bit. I do both the Julian and Gregorian calendars in both AD and BC infinitely into the past or the future.

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@thecalendarninja
@thecalendarninja - 04.11.2022 01:25

I do other cool tricks that aren't heard of very often, for example since this calendar math can be viewed as just a simple addition problem, we can also solve for a missing value using subtraction! For example, if we already know the day of the week to be Friday for example, we can solve for a possible month/months or even a date from 1 to 31 or even a possible year or century.
Example: Which month or months did Friday the 13th fall on in 1899?
1899 was a Tuesday year (-2+4=2) or (5-3=2). So, Tuesday was the 10th since 3 days later was Friday the 13th.
So, 2+13+x=5 (Friday)
x=4 because 15+(-10)=5
-10+14=4
Mod7 arithmetic
Only January and October had a month code of 4 😁. So it only happened twice that year, in January and in October. Also we can say more intuitively that since 1899 was a Tuesday year, and Friday being 3 days later, which month/months had the Doomsday of 3,10,17,24,31? and obviously that is only January and October.
If the question changed to what were all of the Fridays in January and October for example in 1899?
We can say "the 6th, 13th, 20th, and 27th"
If someone were to instead ask for example on Friday the 13th from 1883 to 1900 what year/years did that happen?
We can say "only in 1893 and 1899"
In this situation we just needed to find the missing year code of (4 or -3) and only 93 and 99 have that year code in that date range. Likewise, we could have instead solved for the century 😉 also if already given a year.

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@thecalendarninja
@thecalendarninja - 03.11.2022 22:09

I simply use a version of Conway’s Doomsday Algorithm that i adjusted a bit. I can calculate any day of the week in just a second or so infinitely into the future or the past for both Julian and Gregorian AD and BC as well.

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@caspermadlener4191
@caspermadlener4191 - 03.11.2022 01:25

My method, which I discovered myself, for the day in the year, if the year is between 1900 and 2100 (which means no weird or annoying dates). I wrote it c++ style, which should be easy to follow, because I don't know c++ either.
x=months
y=years–1900

If x>2:
x=x–3

Else:
x=x+9
y=y–1

The date is:
z+⌊z/4⌋+2y+⌊(6y+4)/10⌋+days (mod 7)

I can't remember the day it should be on, but using my algorithm, today (Wednesday) is
5+16+122+30+2≡0 mod 7, so Wednesday is at 0 modulo 7. This means that you need to add 3 to get to the intuitive date, where Wednesday is 3 modulo 7.
My algorithm is not onky much shorter, it is also a lot faster. Try it. I won't spoil the date :)

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@boharakrishna1653
@boharakrishna1653 - 02.11.2022 14:04

It excellent and elated method brother. Keep it up bro.🥰

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@kanchanamonhar8714
@kanchanamonhar8714 - 01.11.2022 06:50

Sir can you please teach aptitudes??

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@kapilsharma3498
@kapilsharma3498 - 29.10.2022 13:57

Amazing .. u super... so much good

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@devpatel6867
@devpatel6867 - 29.10.2022 07:09

Thank You ❤, It helps to impress my friends. I really enjoyed it.

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@vitthalrastogi2829
@vitthalrastogi2829 - 28.10.2022 18:08

Your birthday is on Thursday

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@vitthalrastogi2829
@vitthalrastogi2829 - 28.10.2022 18:08

Your birthday is on Thursday

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@shashwatgupta3105
@shashwatgupta3105 - 28.10.2022 17:59

While calculating the day for srinivasan ramanunjan why did we add 3odd days for the year 1800 shouldn't it be 4 odd days

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@Aditya-supra
@Aditya-supra - 28.10.2022 17:45

Sir I got 80/80 because of you in 1hour in my class thank you sir we will support you but you upload Daily video please

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@physics6374
@physics6374 - 27.10.2022 18:59

I understood the concept sir thank you so much sir.
From your channel i learnt so many mental math sir.
Thank you sir

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@jigmenamgyel2128
@jigmenamgyel2128 - 27.10.2022 17:53

Big fan you 🙇

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@jigmenamgyel2128
@jigmenamgyel2128 - 27.10.2022 17:53

I am in class 10

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@jigmenamgyel2128
@jigmenamgyel2128 - 27.10.2022 17:52

Can you give me tips

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@jigmenamgyel2128
@jigmenamgyel2128 - 27.10.2022 17:52

Hello matho genius
I am big fan you and always waiting for your new video!
I have gain a lot of inspiration of maths from you!
I have maths competition next week and i don't know what to practice

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@marinique.s.whymns.917
@marinique.s.whymns.917 - 27.10.2022 16:51

Blessed solar return, my sincerest wish is that your life will continue to be filled with many more years of elation.
May this day be an occasion for you to realize all of your desires for elation and manifest marvelous things.
I wish you tremendous success in all endeavors you undertake soon, and may God continue to bless you abundantly.
Have a blessed day

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@tejalpatel7424
@tejalpatel7424 - 27.10.2022 16:08

❤️

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@Adityaaa640
@Adityaaa640 - 27.10.2022 16:08

Noice

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@thvsrq
@thvsrq - 27.10.2022 16:07

thank you so much sir , you've teached me so much more than my teachers

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@AyushYadav-ot4ew
@AyushYadav-ot4ew - 27.10.2022 15:42

Sir meri attendance lagaiye👍🏻
Amazing Video to amaze friends 😍🔥
This is a time of celebration of Diwali and other festivals.
May the lights of Diwali brighten each day of your life🪔❤

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@gunjavenugopal9576
@gunjavenugopal9576 - 27.10.2022 15:38

It’s been a year and thanks

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@maanasdongre1581
@maanasdongre1581 - 27.10.2022 15:02

22 July 1999 is Saturday ig

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@khushwant3521
@khushwant3521 - 27.10.2022 14:45

THANK YOU

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@Mikeymouse1
@Mikeymouse1 - 27.10.2022 14:19

Wow I learn something new every time I watch your video. Keep it up👍

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@DIVYANSHJEE
@DIVYANSHJEE - 27.10.2022 14:16

Which country do you live ?

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