Calkin-Wilf-Newman function or something

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The discussion centers on the Calkin-Wilf-Newman function and its application in expressing irrational numbers, specifically π and e, in a rational format. Participants clarify that the function f(x) = floor(x) + (1 - [x - floor(x)]) can be used to derive exact representations of these numbers. The consensus is that for π, the professor requires the expression to remain in its symbolic form rather than a numerical approximation. The example provided for e illustrates the method effectively, yielding f(e) = 5 - e.

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Calkin-Wilf-Newman function... or something

Homework Statement


I have no idea what this has to do with our current chapter in Calc II but it seems simple enough.

[PLAIN]http://img253.imageshack.us/img253/2192/mathv.png


Homework Equations





The Attempt at a Solution



I managed fine for the first two, but I have no idea what to do for pi. The only way I can think to express pi as a rational plus a number is 3 + (pi - 3). Evaluating their function for that A and B can't give me an "exact answer" which is what they ask for.
 
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1MileCrash said:

Homework Statement


I have no idea what this has to do with our current chapter in Calc II but it seems simple enough.

[PLAIN]http://img253.imageshack.us/img253/2192/mathv.png

Homework Equations


The Attempt at a Solution



I managed fine for the first two, but I have no idea what to do for pi. The only way I can think to express pi as a rational plus a number is 3 + (pi - 3). Evaluating their function for that A and B can't give me an "exact answer" which is what they ask for.

f(x)=floor(x)+(1-[x-floor(x)])
After, this change pi into it's series form to get infinite rational expressions although I'm not 100% sure if a change is required.
 
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You don't need the series form for pi.
I'll show you how to do it for e = 2.7818... and you can see for yourself how
to do it for pi.
The integer part of e is 2, so here A=2, B=e-2.
Thus f(e) = A + (1-B) = 2 + (1-(e-2)) = 5-e=2.21...
(and yes, I'm the Calkin in Calkin-Wilf-Newman).
 


calkin, welcome to PF.

I think people may be overcomplicating this problem. By "exact number", I think the professor just wants students to write π as π, not as "approx. 3.1415" or "3.1415...".
1MileCrash said:

The Attempt at a Solution



I managed fine for the first two, but I have no idea what to do for pi. The only way I can think to express pi as a rational plus a number is 3 + (pi - 3). Evaluating their function for that A and B can't give me an "exact answer" which is what they ask for.
You have found that B = π-3, which is an exact number. So what is 1-B here?
 

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