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Vega
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It is a simple little test. All you need to solve it- logical thinking.

A- is a rational number.
B- is an irrational number.

You must prove that the sum of A+B or the difference A-B is an irrational number.

Krisi
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### Re: test for your logic

Xkalibur wrote:It is a simple little test. All you need to solve it- logical thinking.

A- is a rational number.
B- is an irrational number.

You must prove that the sum of A+B or the difference A-B is an irrational number.

Difficult Xkalibur!
As I understood it, the sum of a whole number plus a non-terminating (not sure of term) decimal will be an irrational number.
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Vega
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### Re: test for your logic

krisi wrote:Difficult Xkalibur!
As I understood it, the sum of a whole number plus a non-terminating (not sure of term) decimal will be an irrational number.

Yep.

Should I tell how to prove that or wait for some replies? I will tell you tomorrow.

Krisi
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### Re: test for your logic

Xkalibur wrote:
krisi wrote:Difficult Xkalibur!
As I understood it, the sum of a whole number plus a non-terminating (not sure of term) decimal will be an irrational number.

Yep.

Should I tell how to prove that or wait for some replies? I will tell you tomorrow.

I can wait Xkalibur. Yes, better to wait for some more replies..
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denvinbo
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### Re: test for your logic

A hard test................
Hey! I'm stuck! Get me out!

PIETY-The stories of parents and children

Vega
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### Re: test for your logic

denvinbo wrote:A hard test................

Are you a schoolboy? What grade?

denvinbo
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### Re: test for your logic

9th.........
Hey! I'm stuck! Get me out!

PIETY-The stories of parents and children

Krisi
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### Re: test for your logic

Xkalibur,
Do you want a numerical value to prove it?
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Krisi
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### Re: test for your logic

Xkalibur,
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Vega
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### Re: test for your logic

krisi wrote:Xkalibur,
Do you want a numerical value to prove it?

No, there's no need for it. I'll show you how to do that in a logical way.

A- is a rational number.
B- is an irrational number.
==============
A+B or A-B

1. Let's presume that sum A+B is a rational number:

A+B=C

C-> rational

2. If so, then B:

B=C-A would have been also rational as the difference of two rational numbers, but isn't so because it contradicts to the statement (B- an irrational number). Thus, our presumption was false and therefore sum A+B is an irrational number.

(A-B is similar to the above.)

Simple, isn't it?

Krisi
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### Re: test for your logic

Xkalibur wrote:
krisi wrote:Xkalibur,
Do you want a numerical value to prove it?

No, there's no need for it. I'll show you how to do that in a logical way.

A- is a rational number.
B- is an irrational number.
==============
A+B or A-B

1. Let's presume that sum A+B is a rational number:

A+B=C

C-> rational

2. If so, then B:

B=C-A would have been also rational as the difference of two rational numbers, but isn't so because it contradicts to the statement (B- an irrational number). Thus, our presumption was false and therefore sum A+B is an irrational number.

(A-B is similar to the above.)

Simple, isn't it?

Yes, yes. Got it!
Thanks.
esl member since 2007