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#55951 Re: Puzzles and Games » Connotations. » 2009-05-06 09:47:37

numerics

mediterranean

myth

#55953 Re: Puzzles and Games » Connotations. » 2009-05-05 15:43:59

improbable

Boardwalk

antler

#55955 Re: Help Me ! » Need help on Polynomials » 2009-05-05 00:30:00

Hi 1a2b3c2212;

  Look at my post, it is what he/she may have been thinking about when he/she solved the problem.

#55956 Re: Help Me ! » Need help on Polynomials » 2009-05-05 00:25:09

Hi 1a2b3c2212;

  That statement is not true. Mathsy did not mean that.

#55958 Re: Help Me ! » Need help on Polynomials » 2009-05-04 06:02:04

Hi 1a2b3c2212;

Good answer mathysperson,  that is the way. In case you can't follow it, I think this is his reasoning. Normally to find the independent term (constant term) you would just set x=0, but that is not possible here, because of the x in the denominator, Start with the binomial expansion of.

The general term is:

with



So:

Pull out of the brackets all the constants and get them on the left

Set the exponents of

and
equal to 0

Now just plug into (A).

#55959 Re: Help Me ! » Implicit Differentiation » 2009-05-02 18:41:33

Hi ilovealgebra;

I was doing a similar problem a couple of days ago. I found this then:
http://qaboard.cramster.com/calculus-topic-5-164162-cpi0.aspx
this should give you everything you need.

#55960 Re: Introductions » Hi to everyone » 2009-05-02 10:54:30

Hi ToneMU84 and Ninja101

#55962 Re: Puzzles and Games » Find all triples » 2009-05-01 13:26:51

Hi Tony123 and mathsyperson;

This is a problem by Erdos, who conjectured that

would always have a solution. He did not suggest how many of them there are or how to find them. I also could not find any additional ones other than what mathysyperson has found.

#55963 Re: Help Me ! » Question on improper integrals » 2009-05-01 01:01:47

Hi coffeeking;

That integral from 0 to infinity can be done analytically( the answer wil be in terms of the gamma function) . It is ≈ .232. Concentrate on the integral from - infinity to 0. That one does not converge.

#55964 Re: Help Me ! » Geometry: The missing angles of a quadrilateral » 2009-04-30 17:55:47

Hi Stefani;

After following coffeeking's suggestion, as this is the standard way of doing it. Extend the line FN to point G. Then extend the line MN to point H

Angle FNM is 42 deg because FN bisects the angle KNM, HNG is also 42 deg because vertical angles are equal. MNG is just 180 - 42 = 138 deg

#55965 Re: Help Me ! » Finding the variable in an algebra equation. Please help » 2009-04-30 07:05:44

OK, I need some help here. Kris' problem is an identity, the RHS reduces to A. Does that matter?

B=1 and A>B will satisfy the criteria that

#55966 Re: Help Me ! » Real Analysis Help » 2009-04-29 07:12:07

Heres how to find the limit:

Now make the substitutions

Plug them in (A). This is the new limit.

Now since (B) is of the form 0/0 we can differentiate the numerator and the denominator with respect to u. This leaves:

#55967 Re: Help Me ! » Real Analysis Help » 2009-04-29 02:36:50

I think that if you prove that the limit equals a/2 with a being a positive number you will have proven that the sequence is bounded and convergent.

http://www.sosmath.com/calculus/sequence/limit/limit.html

#55969 Re: Help Me ! » Help with TI-89 converting expressions » 2009-04-28 16:54:04

Hi sumpm1;

   Calculators and computer algebra systems solve problems using very different methods than the human way. They have their own standards for simplification, often this will look strange. The TI 92 which is the bigger, stronger brother of the TI 89 does the exact same thing on your example. Try to use your graphing calculator to augment and check your work. Never let it replace your brain.

#55970 Re: Introductions » proving inequalities » 2009-04-28 16:34:13

Here it is:
http://en.wikipedia.org/wiki/Inequality_of_arithmetic_and_geometric_means

#55971 Re: Dark Discussions at Cafe Infinity » Optical disc offers 500GB storage » 2009-04-28 14:03:48

I guess people will put 100 movies or so on it. Wow, have never seen that happen to a USB drive.

#55972 Re: Puzzles and Games » find sum » 2009-04-28 13:58:10

Thanks for posing it. It was really a tough problem.

#55973 Re: Puzzles and Games » find sum » 2009-04-28 03:49:30

Hi Tony123;

Start by forming the power series:

This will equal the terms of Tony's series if x=1. There are differences of 4 and 2 in the exponents. The expansion:

Has exponents that differ by 2.

Has exponents that differ by 4. To get differences of 4 and 2 we use a

This has the required differences of 4 then 2 in the exponents.
Now I tried to use integration, differentiation or multiplication by x on (B)
to make it look like series (A).
I couldn't. So I tried

This one doesn't have the required 4,2 difference in the exponents so it can't be right.
When I tried:

This looks good. Integrate this series and you get

(C) is series (A). So we have:

Now we need the integral.

with x=1

#55975 Re: Introductions » proving inequalities » 2009-04-27 01:31:01

Good way to find the minimum without Calculus, Thanks

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