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#51 Re: Puzzles and Games » Add 13 more and post it forever. » 2011-05-14 03:39:21

14703

Hi bobbym,
I hope you are feeling fine today.
I got to go now. I am in the eastern city - Kolkata (Calcutta) more than a thousand kilometres away from home!

#56 Re: Help Me ! » Please help me with this question!! » 2011-05-12 17:01:08

Hi mantastrike,
Have a look at this page http://en.wikipedia.org/wiki/Rule_of_product
Also see the rule of sum.

Hi bobbym,
I wish you good health. Get healthy soon!!!!!

#57 Re: Help Me ! » Integration by Parts » 2011-05-08 03:01:38

Hi Natkirky,

Here are some nice pages on integration. Do not see the solutions of the problems instantly. Give them a try first!

http://www.mathisfunforum.com/viewtopic.php?id=3299
http://www.mathisfunforum.com/viewtopic.php?id=6855

#59 Re: This is Cool » Cool way to square multiples of five » 2011-05-04 00:22:04

I read the first few pages and found it interesting. The author has given some nice practical examples about where this field is used.
I have no idea about computers but he has given some nice information on "small" computer 'Strela'. smile

#62 Re: Help Me ! » Show that Cn is a decreasing sequence of positive numbers? » 2011-05-03 23:56:20

It think it is possible. But you will have to prove it logically. Try it. Try to see the behavior of C(n) graphically for n = 2,3 and then a bit larger.
smile
Come back if you have any problem.

#64 This is Cool » Cool way to square multiples of five » 2011-05-03 23:45:06

123ronnie321
Replies: 5

Think of any number that is a multiple of five.
Eg. - 65.
65 is between 60 and 70. So multiply them in your mind 670=4200. Attach 25 in the end.
∴65²= 4225.

Can you guess why it works?

#65 Re: Help Me ! » Show that Cn is a decreasing sequence of positive numbers? » 2011-05-03 23:15:13

Hi Killbox,

Can you show that C(n) will always be positive?

#66 Re: Help Me ! » Show that Cn is a decreasing sequence of positive numbers? » 2011-05-03 21:30:41

Hi killbox,
I shall show you one of the approach.
Plot a rough graph of y = 1/x. Now you know C(1) = 1. C(2) = 1 + 1/2 - Log2. Note that Log 2 is the area of the graph 1/x from x = 1 to x = 2. and 1/2 is the area under y = 1/2 from x = 1 to x = 2. Thus Log2 > 1/2. Second term is less than 1. Apply similar approach for C(3)

#68 Re: Help Me ! » Which book should I refer? » 2011-05-02 22:13:18

Thank you Bobbym,
I have downloaded the first book Combinatorial Mathematics for Recreation - N. Vilenkin.
I will read it and post any doubts that I have on this forum.

#69 Help Me ! » Which book should I refer? » 2011-05-02 18:54:27

123ronnie321
Replies: 4

I am interested in studying combinatorics from the basics. Any good book for amateurs?

#70 Re: Exercises » Is this cool with you? » 2011-04-29 17:37:48

Hi Bobbym,

Thank you so much for your time!

#71 Re: Exercises » Is this cool with you? » 2011-04-27 21:45:27

Hi Bobbym,
But if you pick any point between P1 and P3 and name it say P5 and then draw an arc centered at B passing through P5, you will find that the portion of arc inside the 1 meter circle subtends at B an angle greater than 41.7. Thus the probability will differ, wont it?

#72 Re: Exercises » Is this cool with you? » 2011-04-27 21:26:40

Hi Bobbym,
In your diagram, n = length of segment BP1 & n = length of segment BP3 are the only solutions for probability = 41.7/360. This is what i think. Am i right?

#74 Re: Exercises » Is this cool with you? » 2011-04-27 02:07:06

Hi bobbym,

I am confused. I do not understand your statement although it appeared correct to me till yesterday-

I believe that all n = 7 / 6 to n = 2.5 and a little bit more than that have the same probability.

dizzy

This is what i think ---- for probability p = 1/6 there will be only one solution n = sqrt(3)
and for a fixed probability p < 1/6 there will be exactly two solutions.

#75 Re: Exercises » Is this cool with you? » 2011-04-26 20:04:47

Hi bobbym,
Yes, I am clear with it now.
I will be back in some time with some drawings. I am a bit busy now.

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