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## #1 2023-09-07 08:49:23

harpazo1965
Member
Registered: 2022-09-19
Posts: 129

### Both Rational & Irrational

College Algebra
Section R.1

Are there any real numbers that are both rational and irrational?

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## #2 2023-09-07 18:57:08

Bob
Registered: 2010-06-20
Posts: 9,719

### Re: Both Rational & Irrational

hi harpazo1965

In a word, no.

The set of rational is all those numbers that can be written as the ratio of two integers:
eg 0.5 = 2/4

The set of irrationals is all those (real) numbers that cannot be so written.
eg   √2.

There is a fairly well known proof that root 2 cannot be written as a ratio of integers.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #3 2023-09-08 07:18:04

harpazo1965
Member
Registered: 2022-09-19
Posts: 129

### Re: Both Rational & Irrational

Can you recommend a good math site or YouTube video clip that goes a little deeper into the realm of real numbers?

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