Functions Part 2

[sasasa123sususu]

this video has for dislikes?

[amifunnymynameisbob]

step by step ooh baby

[theferretkit]

U are really good at making the problems understandable!

[Cletzenbougen]

Sal, why is it, I get it when you do it, but when I try to do it, I don't get it:(

[bebeheuy]

I am very happy to see the vidoe after you give this More examples of solving function problems

[AntoMelta]

I Really Like The Video From Your More examples of solving function problems

[willamricard]

Your Video Is Very Useful Sharing More examples of solving function problems

[imegatrone]

after i watched this video, my insight is very open because the video More examples of solving function problems is very good to give information

[davesphizikal]

Sal, at 8:55 you lost me. How did you get g(h(1))?

[SuperInverted]

Because of people like you, there is a high-quality alternative to standard educational platforms.

Keep up the good work!

[gonchienelmundo]

sal your work is really helpfull... I just can say "infinite thanks"

[xxalliexriotxx]

my algebra exam is tomorrow. this is one of the subjects ive had trouble with. im feeling confident now!!

[ryno123321]

I hope I get a question like this on my exam

[Churluh]

I wish he was my teacher. :(

[12sickmaster17]

Really really helpful! understood it here in 10 minutes, while i couldn't understand anything in class for 75 minutes! Thanks a lot :D

[lvenick09]

thank you so much! my university lecturer is tragic

[TheMasterSlasher]

I GET IT

[MrYou2berz]

thank you! your awesome

[kitzenmovies]

Have you guys noticed we entered an age of free education. That suits people even better than our current system? This is awesome!

[MrDevin666]

I love this guy everyone!

[escogido753]

two people failed their function test

[kesor6]

hard to find comments in here -- BUT -- there is a mistake in the second example, its f(6)=5+3g(6) and not f(6)=6+3g(6)

[jazminalise]

@kesor6 no dude, if x=6, then you substitute every x with a 6 in the equation. In the first one he said f(5) so x=5, but only for that function.

[itsAmonder]

thank god i have to learn this for the sats or something

[kornag5]

hhow do you do an inverse of a function if it is in domain and range it is the only thing i can't figure out i am a freshman in highschool but i'm all honors and only 1 freshman class everything else is sofmore and higher

[zamrock20]

@kornag5 your question does not make sense.. you're asking how to do the inverse of a function if it is in domain and range ? could u rephrase that i could maybe help

[AnotherBrownKid]

lol u suck at erasing!

[ThaBoobyWatcher]

you have saved my enitre math life. my teacher couldnt explain that to me in 14 days to of what you did in 9minutes. love you.

[Jzing29]

tysm=]

[struggler98]

thanks man

[vaahtobileet]

Me + this video = huge hard-on.

[Tshabajuju]

is this a rule that g(x)=1 if x is even?

or is this just an example?

[Nightkzi]

@Tshabajuju It is an example. You g(x) can be anything if X is either even or odd.

[hotvampire1992]

kHAN CAN I BORROW YOUR BRAIN FOR A DAY?PLSSSSSSSSS

[ThisApp1998]

Is there anything this guy dosn't know???

[geerrooo]

I think it is easy but why do professors make it harder for us ...son of bitches

[Bruce222255]

screw my teachers, I am going to slack in class, come home, listen to you and still get A's

[Monobob74]

3 time 0 equals 5? 2:27

[geerrooo]

@Monobob74 3 times zero = zero then zero + 5 is 5 i hope you get it

[residentevilpro75]

you are the best. ever

[awesomezhs]

I finally get it thanx to you, Sal!!! :))

Functions are FUN!! :D

I love f(dog) :p

[777uratza]

u r the best, thank you so much :)

[weeweeweewu]

In the f(6) = 6 + 3g(6)

= 6 + 3 x 1

What happened to the 6 g was being multiplied by? :c

[KyleveB]

@weeweeweewu

6 was even, so according to g, it was one. Hence, the function g with six=1.

[catsandjammer]

holly complexity!! i am at a lose as how to evaluate h(g(-2-1)) ?? i mean stuckness r us i tried using g(-3) but got a sad face help thanks jim

[pufifa]

LOVE U SO MUCH!!!!!

[rpscape]

Sal: Putting fun back in functions

[LowIiet]

he's better than my teacher. :D

[iWriteUinMyDeathNote]

wait in the last example, how did you get g(h(1))?? doesn't that change everything?

[zachfigiel]

You're the best Sal

[2vikki]

how would i solve:

for what values of x is f(x) =1 over x-2 defined find 2 values of x such that f(x) is an integer.

(over means like over as in its a fraction so 1 is divided by x-2)

[timmyward215]

Hey, where did part 1 of the Functions series go? Thanks.

[2vikki]

@timmyward215 its called introduction to functions:)

[teerna1]

@timmyward215 It's titled ''Introduction to Functions''

[babynavy771]

study functions = done ... next topic :D

[doorfridgemagnet]

Absolute MIND FUCK MAN thanks!

[AkeeMeCoX]

3:20 - 6:20

ITS LIKE INCEPTION!

a dream within a dream within a dream

h[g(3)]

[paulceltics]

thanks a lot for everything

[Carlhockey1]

your awesome! WAY BETTER THAN MY MATH TEACHER!

[narcomanel]

f of dog xD

[EllieEatsStars72]

I adore you, i would've failed if it weren't for you :'D Thank you <3

[EllieEatsStars72]

Dude, that Sal food, example was like the best example ever.

[kermitcintronsucks]

This was really hard until...BOOM got it. CLICK! EASY! muy facil. facile. leicht .

[whisper012]

haha 3 x 0 = 5 :) Oh Sal

[Danjaboyz]

thanks for this man, it was really helpful

[KathrinHart]

I liked the food Sal example....It helped. And it was funny Which made me want to watch more.

[jadawo]

Who are you so awesome?!?!?!

[tikitorch143]

You should do Variations on Functions... I just finished those.. and once I understood I was like.. oh DUH~ XD Thanks for the help!

[sgt7]

Good demo, thanks

[maddcat0]

in the big long function equation where you were finding h of x, it would have been more helpful to use a, b, and c instead of all x....would that be allowed? or is it always x?

[5UF14H]

@maddcat0 it has to be x. because if you use a,b and c then we cannot substitute a into b because a does not equal b. Whereas using x means you can substitute the same x value into any of the functions since x = x. Sorry if i confused you more.

[fungsit]

i'm 27 years old, Chinese, going to learn math all over again, sal's videos helped me a lot , i think math should be as interesting as how sal explains math problems, kudhafiz !

[Poleschs]

@fungsit Do you eat insects?

[fungsit]

@Poleschs yea, i do, i eat cockroaches, locusts, earthworms, slugs and your mom.

[Poleschs]

@fungsit That's a hell of a diet.

[GigantoGamesReviews]

@fungsit Chinese people say kudhafiz as goodbye? Dude my language is Farsi and I say kudhafiz too =D

[fungsit]

@GigantoGamesReviews, really? I learned the phrase from my in-law family who speaks Bengali. Thanks for telling me that Farsi has that phrase too.

[fungsit]

@GigantoGamesReviews do you use Gtalk ? you can add me, i would love to talk with you about languages!

[amyzactress]

you may not know this but you are saving my life!!!

[theOman333]

the sal food was helpful lol, don't stop it, it makes learning entertaining

[3vikramkumar]

u made me realize....''learning is fun''....thanku Sir ... thanku Brother.... 

[vnscyber2]

Thank you very much for your benignant demeanor, I really appreciate it.

[DarthAndre24]

DOG

[somekid1564]

i love u dude.

[sebzavoico]

HOLY MAN ON COMPUTER SCREEN. u make me understand

[Ovro95]

You are awesome :) I love you ?? What is your email ID ?? I wanna contact with you....you Highlighted Bangladesh !!! :) Thanks !! We are proud of you :)

[Ovro95]

You are awesome :) I love you ?? What is your email ID ?? I wanna contact with you....you Highlighted Bangladesh !!! :) Thanks !! We are proud of you :)

[MrAlexMogil]

Can i just send you some omeny? great work!

[jtpoiyu]

This is awesome, though i think this might be too easy for me. I'm in precalculus. i Hope you got some videos for that edition :)

[Ermal8711]

How would I find fog if I am given set points instead of an equation? In the question i am asked to solve FoG when f = {(-1,2),(0,7),(2,5)} and g = {(-1,1),(3,0),(4,-1)

[RickWheeler9001]

thanks man that helped a lot.

[dragonnite20]

I feel like a lot of teachers at my school became teachers for the 2 months off in the summer and they don't have a passion for teaching nor do they care how they teach it. I tell all my classmates to go to your website and now we're all putting a's on paper and my teacher thinks it's her doing. Don't worry Sal, I won't tell her it's you! :)

[PyroSyndrome]

a friend told me about khanacademy , but i still dont get F of X , westarted it on monday and i still dont really get it :(

[VeniasHD]

Your videos are fantastic. They helped me get into Math Advanced and several A's on Tests.

[MsTriara]

I love you! I'm so gonna major in Maths & Stats now!!

[LancerZEV]

I LOVE YOUUUUU

[raptors551]

nice video mann, soo helpful

[eunice1500]

ur great man, really great

[sadat417]

great video it helped me alot. thanksss

[monsterwasim]

OH MY GOD U JUST MADE A FUNCTIONS GURU!!!!

[bladybrunch]

sal <33333333333333333333333

[Getanniemated]

dude you saved my life



[yashara21]

MARRY ME!!!??

[geminibubblegum]

LOVE

[binahockeybeast]

for reals the Sal/Food example had me listening! It helped me get functions better as well as entertained me! thanks so much for taking the time to do all these Vids!!!

[Ilir7777]

LOL this is baby thing :p

[shrimpay432]

WOW!!! ur vids helped a whole lot. It seems so simple to me now

Keep it up

[Pijjpin]

I got the idea...i am starting to get functions...

[josuanette]

thank you for the presentation. It help me a little ! i want more !!!

[MrSaniful]

Great videos Sal, Thank you very much .

[jenish4]

excellent video, thanks very much!

[GetMeThere1]

useful to notice that f(x-3) =/= f(x) + f(-3)

[partylikapianist]

man!! i wish i found ur vids like....3-4 months ago... they are very helpful.. thank u for the time

[koriko88]

The food example made this more clear than anything else I've ever heard.

GO SAL! :-)

[MikeMandt]

Hey man, no worries on the food poisoning death example. I thought it was funny. worked, too. i am now the functions jedi.

[C3P0meetsData]

@MikeMandt unless of course you use poison, in which case you are the functions sith lord

[manageo]

@MikeMandt may the fundamental forces be with you

[astt171]

Thank you so much for these helpful videos. I always watch them and I learn more from your videos than I learn in class. I hope these videos are always up.

[yellowhat4]

@astt171 I agree

[xibbox]

I LOVE U MAN I FUCKEN LOVE U

[elpollofarzante]

in your 1st example, what happens if x is 0?

also, does this example come from binary computing at all? maybe it's a stupid question... thanks for all your wonderful videos.

[dycarbon1]

0 is even so g(x) would equal to 1

[vkain100]

Didn't understand the g(h(1)) part

[goleyakh7]

Hi, Hope you find this helpful

what is g(h(1))?

First we need to find the amount inside the brackets which is h(1).

We are given h(x)=5x so simply substitute x by 1 in h(x)=5x h(1)=5*1, h(1)=5

now we need to find g(5). We are given that

g(x)=2x+f(x-3). We simply substitute x by5. so g(x)=2(5)+f(5-3)

g(x)=10+f(2)

[mrhnm]

it seems that a function is just a way of saying that the vairable [f(x)] represents a phrase of equation. Is this true?

[mrhnm]

is a function always a letter then x i.e l(x) or h(x)? So you are only replacing x in the equation?

[flufydude]

If i get my math teacher fired can YOU come teach??? please?

[gneric187]

can you take a function like this?

h(g(3) +3 + f(h)) use a function on an unknown value?

[Ormaaj]

gneric187:

That is similar to something called a recursive function. Your innermost 'h' has no input so it isn't a well formed formula.

It would end up expanding to something like:

h(g(3) + 3 + f(g(3) + 3 + f(g(3) + 3 + f(g(3) + 3 + f(g(3) + 3 + f( ...

etc etc etc. It would never end because you can't determine an ending value.

Recursive functions include themselves in their definitions, but also have a base value so that it ends eventually and a result can be determined.

[MoodyTheOnly11inWpNs]

awesome explanation- great posting

[lyleh2]

yoyo ji m getting a head ache from u kid

[GailyMcFlyJonas]

Hey, thanks for posting this btw :)!

i'm stuck on my maths homework, about functions, sadly i've already done the questions that this video is talking about :(

I was stuck on another type of question, lets just hope i can speak to someone :)

keep up the work though :D !

xPEACEOUTx

[GailyMcFlyJonas]

I got help :D

thank you again (a] :D

xPEACEOUTx

[MilwaukeeFtw]

where's part 1?

[MilwaukeeFtw]

nvm, didn't see "introduction to functions" =P

[dpjones00000]

functions are not fun!!!

thanks for vids tho, gonna get me through my maths resit ^.^

[marcusjhung]

Me(math videos(sal))) = food?

[Bloodsaberxy]

you're such a great and influential person

[Gamberri2008]

your're awesome hopefully with these videos and doing some of my book problems, I'll pass my pre-cal class!

[123markanthony123]

Whats that program he uses to write?tell me please...

[Dsrdic]

He uses paint. You can tell on the video CNN: Understanding the Crisis

[MarriedtoMDC]

I'm studying Pre-Cal this summer. Thanks for these videos! Math seems enjoyable again!

[AscendantX7]

i love you sal.

[23davidbeckham07]

nicely explained! =) just need bit of practice and im good 2 go !

thanx sal!

[greeve234]

thanks sal i habe been having trouble with this

[kara507]

omg i've been working all weekend on this stupid take home test cuz my teacher at college is HORRIBLE! and I finally got a problem done and i think it's correct!!! THANKS SAL!

[TheDeathofGrace]

functions are fun right now but only because they are easy im sure were about to face hell in the next two vidoes

[ikester27]

Thank you for this math academy. I am tutoring 8th and 9th graders in algebra. I have not had algebra since about 1966, so I have been lost much of the time. Your videos are easy to understand, and have given me some ideas to increase my students' understanding. Thanks!

[foxfootball30]

Thank you! I'm a freshman in Geometry right now and I was worrying about functions from Algebra 1. I will definately be watching more of your videos when I start Algebra 2.

[bhenedick]

Thanks for This vid. bro!

I've seen your examples in my examination, I wish i had watched this one earlier.

Thanks Again!

[bdub24j]

Ahh...I see now. This problem in particular, is like a three part riddle, but you have to have the key/answer in order to move on and solve the next one.  Confusing, but nice. Once again you've helped me in understanding my math issues. Thanks!

[Solthiel]

Hey man, I really appreciate your videos. I got a really poor teacher this semester in college and she didn't teach these concepts very well. But thanks to you, I understand them more intuitively. You are clear and concise.

[AlaskanGirlForever]

You give the BEST examples!!  Please keep the videos coming!! = )

[supremortal]

sal, there is no need to apologize!! your videos are really really helpful whatever the example is!!

[abedbae]

Oh my goodness its the earliest known prog language. LOL

[abedbae]

You're* hehe

[abedbae]

Your the best.

[123markanthony123]

Thanks! xD

[lajungesombre]

dont apologize! it was hilarious! sal of food. sal of poison. you get the point... lol it was absolutely funny

the sal(education)=learning

you rock man. you honestly do. dont apologize so much! you are a wonderful human being, a wonderful animal, a wonderful part of the universe. stay beautiful inshallah.

[foreverblue04]

you're the best^^

[vickiormindyb]

I hated Math until I started doing your course.

I've had only one teacher, Miss Ravitsky, who made Math seem fun.

Now I sort of like Math, not as much as I enjoy English but a lot more than before.

It's because I'm not frustrated anymore.

Your videos helped me master my frustration.

[ixach]

Thanks again Sal. This video helped me clear a few doubts. I can now realize functions in a breeze. ;)

[vickiormindyb]

I hope this doesn't offend you, but you go so fast I get lost.

I don't know if it's from the accident or if I was just born w/ a slow brain--though the accident did decrease my former speed of thought--but I'm having all kinds of trouble keeping up w/ this.

I've liked everything else about these Math courses, but Functions are way down there on my list of favorite Math problems.

That's how I feel now, but I'm hoping I can change that as I move further along this Functions path.

[5iftyse7en]

you make maths fun! man i so want to be tutored by you!

[vickiormindyb]

You're hilarious: f of dog :DDD Though I prefer f of cat (or tiger) :p

[runescapenerd777]

would this be the same procedure u do in y intersect form ?

[WorldCollections]

Wonderfullllllll !!!

[kamijitsu]

at the end, shouldn't it be 10(5) not 10 + 5?

idk im probably wrong

viva Sal!!!!!!!!

this is a great video & yo