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

Introduction to surjective and injective functions

Watch the next lesson: https://www.khanacademy.org/math/linear-algebra/matrix_transformations/inverse_transformations/v/relating-invertibility-to-being-onto-and-one-to-one?utm_source=YT&utm_medium=Desc&utm_campaign=LinearAlgebra

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### 34 Responses to “Surjective (onto) and injective (one-to-one) functions | Linear Algebra | Khan Academy”

1. Python Cure says:

Hiooii

2. Blasted Shark says:

That guy who never gets mapped to is me

3. Zeina Ayman says:

These comments make me feel young

4. Priyams Bajracharya says:

Anyone in 2021?

5. shreya bayari says:

on point and short. Loved it!

6. Alperen Hyper says:

saolun hocam

7. ab says:

midterms tomorrow thanks for this ^^

8. shu says:

why does sal have such a beautiful voice

9. Jigyasa Chopra says:

Thank u sir! Well explained ❤️

10. chemical bank says:

what does it mean * mapping from the x set to y set* and also f of x is equal to y

11. Jennifer says:

i'm taking online discrete math course rn due to covid, prof posted lecture, but couldn't understand any. Thank you for posting videos abt this.

12. Aadharsh Balasaravanan says:

We can't get videos like this even one of the paid applications that u would have.

13. Aadharsh Balasaravanan says:

Great person.

14. FRANXIS says:

Still can't conceive how the people in these maths videos can write using a mouse like it was a pen

15. Samurai7 says:

Explained very clearly

16. Harsh Kumar says:

Bio students: that's Amoeba😂

17. stephen awuah says:

I have a question
How do u know that the codomain is the same as the range

18. stephen awuah says:

I have a question
How do u know that the codomain is the same as the range

19. s sanjay says:

This 9 min video= 2 hour lecture

Thanks

21. CryoniX says:

I thought Injective (ie not Surjective) meant that Y can't have many X. From what I know, what you are describing at 3:55 is a general function.

22. Raj Kumar says:

Woah it's 11 years now!!

23. BE LOGICAL says:

will someone plz tell me how can two differnt values of x give same answer in a function? i mean how can4 and 5 both map to D

24. 7ANKOUCH says:

Thank youuuuuu my I undrestand now

25. BrittBratt3000 says:

So the image = range?

26. Luka Zec says:

Gosh thx Khan academy! Amazing and easy way of explaining just what I needed to get back on track

27. Deatrix says:

but how do i translate this from a more complex problem? what if f : x —> x and f(x)=3x and x are real numbers? is there a video that addresses this sort of problem?

28. chinmay bhat says:

Dear Sir,
Why the Video Audio is not supporting in Google chrome ?? Kindly guide me in this issue

Thanks & Regards,
CHINMAY N BHAT

29. KAIZER MARTINEZ says:

What if one of the x elements is not associated to any y elements? Is it a function or not?

30. Erick Cabrera says:

KHAN YOU ARE THE GOAT!

31. J P says:

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.

32. sreelekshmi ms says:

Thank you 👏

33. Shuvo Sarker says:

Watching Khan's videos are like eating raspberry pie or like listening poetry.