Proof that there is an irrational number between any two rational numbers : Khan Academy on a Stick

Khan Academy on a Stick

Rational and irrational numbers

Introduction to rational and irrational numbers
Recognizing irrational numbers
Sum and product of rational numbers
Proof that rational times irrational is irrational
Proof that sum of rational and irrational is irrational
Proof that square root of 2 is irrational
Proof that square root of prime number is irrational
Proof that there is an irrational number between any two rational numbers
Recognizing rational and irrational expressions example

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