Proof that sum of rational and irrational is irrational | Algebra I | Khan Academy

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[bozeiky]

Low key discrete math help too. Thank you!

[oldmusicteacherchick]

Sal. I am so thankful for your video classes. My 12 year old son is very bright but extremely dyslexic. This year he is doing your world history, biology, and algebra classes. He is learning so much from you. Your classes are perfect for dyslexic students. We don't do any work sheets though too hard to decode.

[kooky]

Sal: It is good to see you doing problems in number theory such as the Classic Proof
of "the square root of 2 being irrational" and ones similar to this video. Please continue as they are very mentally challenging  and stimulating. Kudos!

[e-wame]

basically
irrational being - and rational being +
- × + = -
- × - = +
+ × - = -
+ × + = +

[KingZarken]

Thank you for this video! now I get the contradiction thank you!

[science]

No sir, I have counter example,
√2 + (- √2) =0 which is rational

[dr.paddlesmack]

hey sal, can you put up a proof that uses contradiction to prove pi is irrational.

[CabomBaby]

Hmmm, you can just say pi + 1/1 is irrational

[colinjava]

I did it like that in my head before I watched it but it's the natural thing to do.

[theophonchana]

irrational + rational = rational (wrong)