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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.
Jamaican feat!I find this song catchy... just get up on your feet and dance for good health.
Good day!

esl member since 2007

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..
Jamaican feat!I find this song catchy... just get up on your feet and dance for good health.
Good day!

esl member since 2007

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?
Jamaican feat!I find this song catchy... just get up on your feet and dance for good health.
Good day!

esl member since 2007

Krisi
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Posts: 3906
Joined: Fri Jul 20, 2007 9:48 am
Status: English Learner

### Re: test for your logic

Xkalibur,
Jamaican feat!I find this song catchy... just get up on your feet and dance for good health.
Good day!

esl member since 2007

Vega
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Posts: 2254
Joined: Tue Sep 19, 2006 2:59 pm
Status: English Learner
Contact:

### 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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Posts: 3906
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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.