Math Is Fun Forum

sologuitar

Member

Registered: 2022-09-19

Posts: 467

Both Rational & Irrational

College Algebra
Section R.1

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

Bob

Administrator

Registered: 2010-06-20

Posts: 10,198

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

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Children are not defined by school ...........The Fonz
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Sometimes I deliberately make mistakes, just to test you!  …………….Bob

sologuitar

Member

Registered: 2022-09-19

Posts: 467

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?