Hexadecimal number system | Applying mathematical reasoning | Pre-Algebra | Khan Academy

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[@pezpeculiar9557]

Sometimes I wonder how you write so good with a mouse

[@Simon-xi7lb]

+wowitsbryce *Well

[@pezpeculiar9557]

Simon H. You know exactly what I meant.

[@Simon-xi7lb]

wowitsbryce it's a meme you dip

[@pezpeculiar9557]

Simon H. That's not a meme.

[@Simon-xi7lb]

wowitsbryce knowyourmeme.com/memes/grammar-nazi you wot m80?

[@trinex64]

The thing that really impresses me is... how somebody can write beatifuly with a *MOUSE*

[@Tech360HD]

sorry to break your impression,he is using a drawing/writing pad.

[@Ben.N]

@@Tech360HD that would make sense, but in some videos he drags the cursor to the side to switch colors?

[@Sama-tq1nk]

@@Tech360HD I don't think so because you can see a cursor on the screen. So he is using a mouse

[@matthew1992]

@@Sama-tq1nk he shows his setup in a tiktok and he does indeed use a stylus to write

[@tang3151]

@@Sama-tq1nk he uses a stylus, the tip of the pen is responsive to the screen lol no one can write like that with a mouse

[@shayyrenee9283]

I was super confused til I came here. You never let me down , Sal. Appreciate you!

[@tangledrootsmedia]

agreed! First time coming to this channel and the way he teaches is so clear its amazing!

[@mrgenetics4063]

Please stop posting stupidity

[@AdamShaiken]

FF(hex)=255(dec) and AF3(hex)=2803(dec)

[@aldante7079]

Isn’t FF 256 ?

[@juangaming1.0allaround64]

@@aldante7079 FF Reading left to right. First F is 16^1 Second F is F^0 So, F • 16^1 + F • 16^0 F = 15 16^1 = 16 16^0 = 1 Now to simplify. So, 15 • 16 + 15 • 1 So, 240 + 15 Which comes down to 255

[@cloudcop4846]

FF is 255 and AF3 is 2803

[@jaswik2023]

yes v

[@ChimyChum]

Ye

[@unknown-vq1gj]

samething

[@MikeGreenwood51]

Is there a FFF? If yes what number is it? TY.

[@fliptrontube]

@@MikeGreenwood51 15*256 + 15*16 + 15 = 4095

[@MG30001]

ah thanks. now i understand that hex color codes are just representations of ther decimal RGB value

[@dylanvient6360]

So many different paths unlocked in my brain

[@gatoradefanVEVO]

the letter B: B my brain before watching this video: "babababa"

[@medbob1]

Each hex digit represents half of a byte in binary. As a byte is made of of 8 bits, the E7 above can be easily transformed into binary as the first four bits can be represented by the E. And the second four bits are patterned after the 7. That is why Hex is often used in computers as the character representation matches the pattern of bytes exactly in fewer characters.

[@anaa9245]

I just learned this today :)

[@Milstrosity]

I thought school was easy, this is a 6th grader talking though.

[@vitela2745]

I'm E years old and I already know how to use hexadecimal.

[@llamaindustries1]

+Real Constant and? i learnt when i was 10

[@rhodriprice2205]

+llamaindustries soz m8

[@EaglesInHD]

+llamaindustries Lol good for you too kid

[@iamblakepeters8525]

same

[@iamblakepeters8525]

+llamaindustries apparently you took to much time in math, and not enough in english

[@robinlakics4169]

I recently changed mathematics groups and i was told that i would fall behind others and ned private tutoring but after i binged the whole section about this I’m now ahead of my whole class, thank you

[@michaelrogers2597]

I understand how you converted the E7 to 231, I just wish you showed us how you converted the 231 to E7 in the first place.

[@bbsmislive2116]

Michael Rogers

[@dswailes3767]

Thank you! My point exactly. Lousy job in explaining, nothing makes sense from that point on.

[@AgathaNantt]

231/16=14.4375 14=E (in hex) 14*16=224 231-244= 7 7=7( in hex) 231=E7(in hex)

[@R0ssMacPherson]

+Agis beauty Finally. All I wanted to see.

[@tawbinable]

Thanks for explaining. I was wondering how he got E but now it makes sense.

[@technoultimategaming2999]

AF3 A=10 We have 16^2=256 256×10= 2560 F=15 16^1=16 16x15= 240 3=3 So AF3 = 2560+240+3=2803?

[@imanidiot2180]

And your answer is... correct!

[@MikeGreenwood51]

Thank you for showing that!

[@vxrdrummer]

I am here for a refresher of my college days 20 years ago. AF3 = 2803. Blimey that was actually 14 years ago in hex!!!

[@mmm-kh1od]

think it should be 403

[@UltimateBargains]

pronunciation is A: Able B: Baker C: Charlie D: Dog E: Easy F: Fox

[@keonscorner516]

No

[@MG30001]

I was about to ask if F shouldn't be 16? But not no, it starts with 0. So does binary etc. So not "computers start counting with 0", every number system does. Now I even figured out why. Because number sign are just placeholders. And the lowest value you have to represent "nothing" in order to express "no times this power of base jump". Only humans start counting with 1. Seems super logic but who's really aware of it? Mindblowing!

[@MikeGreenwood51]

TY.

[@donnamccormick5515]

Thank you so much, as I was introduced to this system decades ago. So now I can study your very clear lesson, and help myself understand and actually remember this system. The greatest compliment that I can give you is that you have helped me with something that I could never have grasped before, as did Mr. Tuscher in my 1st year of college

[@donnamccormick5515]

... even more decades ago. Thank you.

[@navalporcupine2426]

Thanks, I've got my exam tomorrow and this is somewhere which caught me out in my last mock exam.

[@hslegolos]

are you allowed a calculator in this exam?

[@sushi893]

4 years ago?

[@skywatcher458]

@@hslegolos uhh calculator are using 10 base number, it's not going to help much with base 16 number system

[@sdawasdwaasda8491]

among us

[@MrLlaanderson]

Really appreciate these videos. Wish my course materials made it this clear!!

[@MikeandVille]

Decimal equivalent of "3" = 3 × 16^0 = 3 Decimal equivalent of "F" = (F) 15 × 16^1 = 240 Decimal equivalent of "A" = (A) 10 × 16^2 = 2560 Decimal equivalent of "AF3" = 2560+240+3 AF3 = 2803

[@StewartBroadcasting]

Thanks, helped with my computing class.

[@bbsmislive2116]

StewartBroadcasting

[@gabefimbres]

Ok cool i understand now Ff= 255 (15×(16^1))+15=255 (15×16)+15=255 (240)+15=255 255=255 Af3=2803 (10×(16^2))+(15×16)+3 (10×(256))+(15×16)+3= (2560)+(240)+3=2803 (2560+240)+3=2803 (2800)+3=2803 2803=2803 I was limited on space for that last one

[@user-ew7js9ux9n]

I'm in 8th grade why am I even watching this :/

[@MM-qk8eg]

Thank you for this informative video. Now I know what the hex my teacher was talking about

[@abrpapa]

At the start of this video I was 18 years old, now I am 12

[@rich1051414]

AF3 = (16^2 * A) + (16 * F) + 3 = (16^2 * 10) + (16 * 15) + 3 = 2803

[@calliehatsu]

great video

[@livewithdanishzahoor6347]

Nice🥰

[@MikeGreenwood51]

What is 33.60º? What is 30.82º? Converted to layman sixty degrees mathematics please? Is the 'º' denoting hexadecimal rather than degrees? And if yes. Is reality that 45º is the same in hexadecimal as well as in a sexegisimal degree language system? IE is that just a mathematical coincident? TY.

[@Redorikev_Ranovee]

I'm 10 years old in hexadecimal system..... Convert it in decimal

[@Given_A]

I dislike maths. I am only here because I am learning bitwise manipulation in C

[@James14703]

Great video, very clear and easy to understand. Thanks!

[@nikhilkumar-c7]

what is the application or software or any external device used in this video for writing?

[@Moglikidunia]

Why Base-8 numbers not commonly used in the presence of Hexadecimal number system?

[@mrbale1815]

14*16+7 , so number position is just instruction for multiplication

[@hicmacijom3117]

If get a F in school my grade is 15x 16 =240

[@ArnabChatterjee361]

F means just 15.

[@oliverbeck6839]

so you got 15% , F, nice one makes sense

[@sidney7180]

Go on double speed to 2:15. Still laughing! But a great video!

[@ChrisTarasovs]

you lost me at e7. need to look back at ur videos.

[@Baharuls]

I am B years old and i know how to use hexadecimal

[@fxtly]

Youre B years old?

[@monsterjazzlicks]

Way too complex for such a short duration!

[@IamJenJen101]

in our number system FF is 255 (15*16 + 15*1) and AF3 is 2803 (10*256 + 15*16 + 3*1)

[@IamJenJen101]

I think

[@Soulstealer050]

Iam JenJen It's what I got. FF would be (First F= 15*16= 240) while (Second F= 15). 240 + 15= 255. :)

[@toonaville02]

So for understanding, why wouldn't it be 10*16 for A? but it is for F?

[@IamJenJen101]

Que because A is in a higher position the A is in the two-hundred-fifty-six position and F is in the sixteen position meaning A is symbolizing how many two-hundred-fifty-sixs there are, and not how many sixteens

[@phoenixdzk]

FF=255. So does that mean Red? I think red is 255,0,0 so does that change anything?

[@drofeng]

If you are representing a RGB color using 8-bits, it's FF0000, where the first, second and third bytes represent the red, green and blue value, respectively

[@djprogramer973]

Perfect thank you so much. Hexadecimals went right over my head

[@ekoi1995]

they should invent 16 new unique symbols for the 16 numbers of hexadecimal that would be totally cool

[@tymothylim6550]

Thank you very much for this video! It is very well done and very educational :)

[@RockyLikesPews]

So why is Hexidecimal code sometimes written like this example --> 0x64

[@spaghettiking653]

Just a convention. A programming language once used the 0x to distinguish hexadecimal from normal decimal in the code, though it eventually got pretty popular. Most programming languages use it to denote hexadecimal numbers now.

[@johnsalisbury4420]

Great explanation! Really helped me out! Up until this point I've been using RGB decimal for defining colors when coding in HTML/CSS, but now I can actually understand what I am doing when I use hexadecimals!

[@muffinbunbiz6222]

this is really making me think about life

[@plrokster309]

How about a base e system? That would be useful for natural log sort calculations. Anybody with me?

[@rutabagasteu]

Ultra Takes The L base e. is a non repeating decimal number like pi. is.

[@nayesha9375]

Awesome explanation 😭🙌... It was soo good! I wasn't able to understand anything before !

[@sdawasdwaasda8491]

shut up

[@jimmyjohns2736]

Im sorry but.... 3499 is DAB

[@DELANO..]

your like the cool math teacher everyone wish they had :') lol

[@h7xmdxnn]

Lol

[@tsundor1]

some people here are saying their ages in hexadecimal as in A,B and C and stuff. I'm 16. nothing special about that..

[@Cosmic_Mario_]

Tsundere Dorito ur F

[@profortnitestreamer8894]

You'd be 10 years old

[@johnjackson3483]

You totally don't get it. A location in memory called an address in an 8-bit computer looks like this 0000000000000000 through 1111111111111111, but it becomes much easier for programmers to break it down like this; 0000 0000 0000 0000 thru 1111 1111 1111 1111. Then we can abbreviate so our addresses loke like this; 0000 through FFFF. This indicates a location; we aren't so interested in the value of the number.

[@DTROIY]

your so good with a mouse

[@TwoAwesomeKids34]

The only thing that stresses me out is how good you can type with a mouse you monster

[@rubikfan1]

Maby he uses a digital pen?

[@mikearchives]

The way I go from decimal to hexadecimal is by converting the decimal to binary and then binary to hexadecimal. The reason is because every nibble of binary maps directly to one of the 16 hexadecimal digits. Is that the most efficient way of converting?

[@Unstopapple]

No, every base is convertable to each other. The only reason we use one over the other is its primary use. Electricity is on or off, so we use binary, binary is commonly used in packets of 8 bits, or 1 byte, so we can represent half of a byte as one digit of hexadecimal. So FF means 1111 1111 in binary, and is used in compacting the information computers use. It is easier to read F2B9 than 1111 0010 1011 1001

[@Valentina-cl1fv]

GenOmega2 That's a really interesting comment. Thank you :)

[@alexanderjunior9442]

Please Guy's I need your help. How do you convert 231 to hexadecimal. I didn't understand it here. Can someone explain to me here please. Thank you

[@badumtiss9834]

We use your website in math class at school. At first I thought is was just another stupid ass math site, but after watching this, I feel different. I'm aiming for a career in computer science in the future, and knowing this is pretty important. You illustrated the way hexadecimal works very well, and I now understand it.

[@creativeclaude5304]

Thanks so much was much more clear when you explained it!

[@wildriftdreamkrusher5801]

i was confused. i came here confused. i saw the confusing video. i got confused by the confusing representative digit. i ended up more confusing myself. did i confuse you? - by confusing confused confuser.

[@uzairsyed8399]

F=225 and AF3=2803

[@cliffordbevans8140]

Maybe a dumb question, but could this system be extended out seemingly infinitely, limited only by the number of symbols invented to represent the different integers?

[@oakenguitar3]

I think the world would be a lot better off if we counted in 12s instead of 10s and our computers used ternary/trinary instead of binary. Base 12 is the best base to use for everyday math in your head. Its a lot easier to learn to multiply base 12 than base 10 which is what we use since 12 is very composite. In base 10, the 1s,2s,5s, 10s, 11s are easy to learn how to multiply since there is a pattern but in base 12, the 1s,2s,3s,4s,6s,8s,9s, As, Bs, 11s (13s in base 10) are all easy to learn because there is a pattern but As and Bs pattern is harder to see. If computers used ternary/ trinary, you could have 0,1, and 2, or -1,0 and 1. The computers would use less energy and be more secure and still use modern coding with some minor adjustments maybe. Every base number system has its own strengths and weaknesses but bases 2, 10 and 12 are super important. base 4, 8 and 16 are good for computers. In Base 6, all the prime numbers greater than the number 6 all end with a 1 or 5 , but not all numbers that end in a 1 or 5 are prime. You can count to 1023 on your fingers in base 2 since your fingers can bend and stand for a 0 or 1 but you can count to 59,048 in base 3 on your fingers if you can make your fingers bend half way or touch a surface to stand for the extra digit.

[@emaknyapororo1660]

Bro u were in the shower for too long

[@sterro8054]

emaknya pororo underrated comment.

[@rich1051414]

The problem with that is, transistors are binary, so making processors to use trits instead of bits increases complexity which would reduce the effective transistor count, which may cause us to be back at square one. Additionally, software has been optimized since forever with powers of 2 in mind.

[@vincenzo3574]

You probabily don't know why computers Count in binary, make them Count in trinary would be a lot harder, in binary is simple, 1= wire with electricity 0 = wire without electricity

[@rich1051414]

That is not why trinary is more difficult. Trinary is just as simple. 0 = wire at ground, 1 = wire at positive voltage, 2 = wire at negative voltage. The problem has to do with the fact that transistors themselves are only 2 state devices. It is a fundamental thing.

[@bmx98583]

So how come computers don't use a 20-bit system or something instead of Binary? Wouldn't it be easier and smaller to transport larger information?

[@VarishtGhedia]

Because if we go towards the lowest level. i.e. the way the semiconductors in our computers operate there are only two states. High and Low or 1 and 0. So we use binary system in the computer. Over the binary system we can use any nth base system. But when it comes to the lowest level we need to use the binary system only.

[@brrrdman85]

At the base level the computer circuits only know on/off, yes/no, etc. They know binary, thus everything is built off binary. It is far more convenient to use hexadecimal (which is mathematically closer to binary than decimal).

[@hyorinxo]

Thank you so much! So easy to understand!

[@trynnafinddso4730]

you guys rock

[@minhvotran1115]

If the letter exceeds the letter F , we just simply ignore it ? How can we deal with it , e.g. 0x43x

[@physicswithShohan]

Thank you so much .This topic is more clear when you explained it !

[@sanjaysinghrawat3363]

Internet is a good place just because of people's like you 💗

[@alberteinstein1015]

You have re-shown me how numbers work at the cost of my newfound discombobulation.

[@mikerockmusic2779]

Thank you for helping me understand this concept, finally.

[@freddyaleman635]

FF = 255 AF3= 1843 o/ Thanks for the video!

[@Goomba1151]

AF3 is 2803

[@magicguycouldbe]

Goomba1151 *3059

[@Unstopapple]

Magic Guy Could Be that is BF3

[@magicguycouldbe]

GenOmega2 oh... woops

[@oscarchivas3123]

If you don't mind me asking, what software do you use to make these videos? My old physics teacher makes videos for his students using a smart board but sometimes parts of the writing cut off and it can be tricky to understand. It'd be great if he could upgrade to something like this

[@jimmyjohns2736]

Oscar i think its in the website

[@abdulazizalrashidi1168]

This wasn't useful!! all you did was proofing the answer, you should have shown the steps of how you got the E7 in the first place? Sorry for the negative comment, please take it as a positive feedback.

[@drofeng]

E7 is an arbitrary hexadecimal number, he just chose it randomly.

[@agstechnicalsupport]

Great explanation of the hexadecimal numbering system. Thank you !

[@sugarfree_]

In base16 I'm 10 years old and in base2 I'm 00010000.

[@TrueMose]

Pay _$15_ to pay respects

[@bruh_itsbella6122]

I didnt understand E7 shouldnt it be 14+7???

[@el_chico1313]

aaaactually these arbitrary ink pieces were invented by the phoenicians ^^

[@gabe9250]

I was trying to do B00 in my head as a practice thinking it would be a smallish number, I get 2816. I guess that’s smallish?

[@fliptrontube]

that is correct

[@alexodonoghue3595]

Really helpful, cheers

[@fahdalawsi2172]

That video helped me in like no time. Amazing job

[@lilsamofro]

Soooo with RGB being measured between 0 -255, im assuming that we use 255 shades of each colour to match the Hexadecimal limit. ie we chose to use hexadecimal first and then decided 255 was adequate rather than a happy coincidence??

[@ameliaring5876]

Fun fact I learnt binary when I was 9.

[@justink7269]

Why did mark watney need base 16 to communicate?

[@stoatsnhoney]

Who else came here because of The Martian

[@timmackie9524]

FF=255

[@fluteloopsyd]

I started texting my friend in hexadecimals just to confuse her. I said, "48 49. 49 55 53 45 48 45 58 41 44 45 43 49 4d 41 4c 53 4e 4f 57 !" which means, "HI. I USE HEXADECIMALS NOW!" It's in all caps because if it weren't, things would get a LOT more complicated.

[@fatalritte1550]

that hexadecimal system is way more complicated than it has to be. I got interested in it from watching the Martian. all you have to do is take the letter F, put the number 10 beside it, and there's your entire alphabet. There would be no need for punctuation or spaces in the message. But I guess it's not unusual for people take something simple and confused themselves with it. I'm still trying to figure how you took "FF" and got the color white.

[@emirsaidhaliloglu2523]

There is georgian, arabic etc translates but not Turkish ?

[@mbenitez6722]

okay I grasp the concept but somehow my programming lab is giving me a problem of hexadeceimals and I keep getting it wrong >:( Write a hexadecimal integer literal representing the value fifteen. ___________________________________ I don't need the answer but I would like some explanation as to why all of my 47 responses are incorrect, I tried everything lol

[@D00MLOORD]

What kind of input device do you use? Looks too smooth to be a regular mouse :)

[@monkeyapex]

I'll be a graphics tablet. Used by digital artist usually. Search it.

[@remielsmetaverse]

very helpful man thanks!

[@fatalritte1550]

that hexadecimal system is way more complicated than it has to be. I got interested in it from watching the Martian. all you have to do is take the letter F, put the number 10 beside it, and there's your entire alphabet. There would be no need for punctuation or spaces in the message. But I guess it's not unusual for people take something simple and confused themselves with it. I'm still trying to figure how you took "FF" and got the color white.

[@Busy422]

Is this type of Math for computer science only?

[@BaBirakos]

Is AF3 2803 and FF 255???

[@tijnieken]

Yes

[@xxcbxxx]

Y is AF3 2803 Y is it not 403?

[@IamJenJen101]

Super Ace 777 please explain how you got 403 if you remember

[@ak1hiro133]

They probably multiplied A (10) with 16 instead of its second power, 256.

[@ViperPilot16]

Not gonna lie, after seeing The Martian (2015 film), I had to try to learn this lol. PS: Sure it's not entirely easy, but it's not really that complicated.

[@tlc1432]

255

[@RaNdOm3.1415]

So we’re combining algebra and counting?