Surjective (onto) and injective (one-to-one) functions | Linear Algebra | Khan Academy

Introduction to surjective and injective functions

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[mahmoudnadi]

For anyone watching; a term that can be used to describe a function that is both injective(one to one) and surjective(onto) is referred to as BIJECTIVE

[plaxen]

this 10 min video > 2 hour lecture

thank you Sal

[larrypark]

dumb f**king textbooks twists the words and sentences so hard that sometimes it is so hard to learn the material (especially theorems and definitions). Thank you Sal for making these videos.

[mauriciobeithia]

My teacher made this way harder than it actually is. Thank you!

[plamenpetrov]

A minute of silence for that guy who never gets mapped to

[gaurav.raj.mishra]

Sal is one of the greatest humans who have ever lived and breathed.

[khanacademy]

rewatch it in a few minutes. should be available in hi-def then

[raz]

You sir are responsible for my A+, I got yesterday!
It was the only concept that wasn't clear even though my Teacher asked me about _"Do I make myself clear, "_ but I'm a shy kind so I affirmed and never got the actual concept!

[ebayaankabir]

This was uploaded when i wasn't even born now its here saving me in my exams.Sal saving generations

[artmasterpl]

Stop scrolling down go back to studying

[dominykasraila]

This lesson is very well explained. Bravo. I couldn't understand the subject reading the textbook but now I can.

[mihurcina]

Amazing. I was sick during the explanation of this at my school and altough english is not my main tongue, this thing made it clear to me. Thanks A LOT.

[jasminemmohsin]

Thank you so I never actually understood the concept to this day. I read all the definitions at least hundred of times and still didn't get it. Watched your video for 10 minutes and finally undersood something that I didn't get in years and years of math! Really, THANK YOU SO MUCH!!

[honeybadger]

Your videos are the best! I wish you could be my personal tutor, I would understand everything so much better!

[jenish]

you're just an excellent techar, why can we have a teacher like you? I was in the lecture room for 2 hrs trying to understand, but I learnt it here in 10 mins, amazing!!!

[jjknow]

from morocco i want to thak you for this clear explanation :))

[TheFlemishNut]

You spend 3:40 just to say surjective means that every possible output of an algebraic expression must have at least one input.

[JP-xmqf]

Wow, this explanation was so clear, much better than my prof. just talking to himself on the board. You are indeed a true saint, making knowledge accessible to everybody.

[yunakim]

Me watching it like 13 years after its upload woah 😂

[InFamousStickFigure]

You might be the reason I pass Discrete math, I thank you time and time again for all your videos to reference.