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#41751 Re: Puzzles and Games » Simple Logic Puzzle; The Farmer. » 2005-09-18 17:29:57

The additional worker is accomodated and the earlier arrangement is changed into this formation:-

          4 workers          5 workers            6 workers

          5 workers          The house            6 workers

          6 workers          6 workers            3 workers

Just a guess smile

#41752 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-18 16:10:43

kylekatarn wrote:

solved problem #k+20  (finnaly, I think)

And solved it correctly! Well done, Kylekatarn!!!

And the solution to problem # k + 2 is a much smaller number!
It is

#41754 Re: Help Me ! » Help in Math Induction Question » 2005-09-15 02:04:44

ganesh wrote:

Put n=7.
7mod6=1
7^3mod6=343mod6=1
Put n=8
8mod6=2
8^3mod6=512mod6=2.
Assume this is true for k.
Therefore, kmod6=k^3mod6.
Try for k+1.
Lets say (k+1)mod6=m
(k+1)^3mod6 = (k^3 + 3k^2+3k+1)mod6.
= (k^3+3k^2+2k+k+1)mod6= (k^3+2k^2+k^2+2k+k+1)mod6

= {[k²(k+2)+k(k+2)]+k+1}mod6
= {[(k²+k)(k+2)] +k+1}mod6
={[(k(k+1)(k+2) + k+1}mod6

We know that k(k+1)(k+2) is divisble by 6 for any k>1, k∈N,
Hence the above is reduced to
(k+1)mod6

It is seen that it is true for k+1, hence, it is true for any value of k.

q.e.d smile

#41755 Re: Help Me ! » very easy problem solving, but I'm just soooooooo bad at this » 2005-09-14 23:45:45

altar wrote:

How about this one?
= {m - [1/3m -4] - [m/6 -2]  /2} -2
The result is given: m/4+1
= {m - [1/3m -4] - [m/6 -2]  /2} -2
= {       2/3m +4  - [m/6 -2]  /2} -2
= {       2/3m +4  - [m/6 -12/6]  /2} -2

= {2/3m +4 - m/12 +1}-2

= {2/3m - m/12 + 5} - 2

= 11/12m + 5 - 2

= 11/12m + 3

= (11m+36)/12

#41756 Re: Maths Is Fun - Suggestions and Comments » The math tag » 2005-09-14 22:13:14

Great....
It would take some time to be familiar with the codes smile

#41758 Re: Help Me ! » very easy problem solving, but I'm just soooooooo bad at this » 2005-09-14 20:42:46

by_Faizah=m-(1/3m-4)/4-3 
This should be written as   {[m-(1/3m-4)]/4}-3

= {[m - 1/3m +4]/4}-3

= {[2/3m+4]/4}-3

= {[(2m+12)/3]/4}/ - 3

= {[2m+12]/12} - 3

= {[2m+12]-36}/12

= {2m - 24}/12

= m/6 - 2

#41760 Re: Guestbook » Math » 2005-09-14 16:26:59

Hi Audrey, welcome to the forum.
We would be glad to help you. You can post your problems in the 'Help me' section.
To begin with, in Algebra, variables such as x,y,z or a,b,c etc. are used to solve problems.
A monomial is an algebraic expression containing one variable, like 3x+8 or 4x²-5x+9 etc.
A Binomial contains two variables like 3x+8y, 4x²-7y²etc.
A polynomial contains more than two variables.
The degree of a polynomial is the highest power of any variable.
There are certain expansions to be remembered.
Like (a+b)², (a-b)² etc. You can find them in your text books.
Believe me, Algebra is both fun and easy. smile

#41762 Re: Help Me ! » Help in Math Induction Question » 2005-09-14 16:16:20

Put n=7.
7mod6=1
7^3mod6=343mod6=1
Put n=8
8mod6=2
8^3mod6=512mod6=2.
Assume this is true for k.
Therefore, kmod6=k^3mod6.
Try for k+1.
Lets say (k+1)mod6=m
(k+1)^3mod6 = (k^3 + 3k^2+3k+1)mod6.
= (k^3+3k^2+2k+k+1)mod6= (k^3+2k^2+k^2+2k+k+1)mod6
= [k(k^2+2)+k(k+2)+k+1]mod6...
Running out of time...gotta leave....

#41764 Re: Maths Is Fun - Suggestions and Comments » Torus » 2005-09-12 21:18:11

Very good work, very nice pictures.
Just a thought....R and r can be illustrated more clearly,initially I mistook them for the external and difference between external and internal radii (we are always more comfortable with 2 dimensions smile) .
New forumlae to remember ......
Surface Area = 4 × π²  × R × r
Volume = 2 × π² × R × r² 
The best part was the metamorphosis of a torus into a sphere smile

#41765 Re: Introductions » Hey guys. » 2005-09-12 20:56:59

Hi Catherine, You can be here as often as you want or as less often as you want. Welcome to MathsIsFun smile

#41766 Re: This is Cool » I discovered...... » 2005-09-12 20:52:08

Sorry, that should read x+ln(x) = 0

#41767 Re: Help Me ! » managment problem. » 2005-09-11 23:53:11

Welcome to the forum, Dr.Dale,
It is nice to know that you intend creating a website with Mathematical formulae;
The best way to do it is recall from memory or refer a standard textbook;
you may also add Theorems/Conjectures/Laws/Postulates and definitions and SI Units too, with pictures wherever required. Values of Scientific constants etc. may also be added.
I think HTML doesn't support certain symbols like pi, phi, theta etc. You would have to take the assistance of a professional webdesigner.
You may also use a search engine to get the desired information from the Net. Care should be taken not to reproduce verbatim as that may amount to Copyright infringement.
You may take the permission from the webmaster to put the information/pictures on your site. From experience, I can tell you that, often, permission is granted for placing a link on your site. In some cases, you may also be allowed to put the information mentioning the source.
However, as a precautionary measure, it is always safe to get prior permission.
The most difficult part is getting the hits. For that you would have to register with Search Engines, some of them provide free registration.

Good luck.

#41768 This is Cool » I discovered...... » 2005-09-11 19:59:49

Jai Ganesh
Replies: 1

I discovered this morning there is a cool website on the net that gives you a lot of information on interesting properties of numbers. There's a lot you can learn, like......
Omega constant is 0.567143290409783872999968662210355549753815787.........
which satisfies each of these simple equations (all equivalent):

e^x = 1/x                               x = ln(1/x) = - ln(x) 
e^-x = x                                              -x = ln(x) 
x*e^x = 1                                        ln(x) = 0 
x^1/x = 1/e                                   x/ln(x) = -1 
x^-1/x = (1/x)^(1/x) = e ^( ln(x)/-x) = 1 


Click here to visit the site

#41769 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-11 00:16:57

Problem # k + 22

Grandpa: "My grandson is about as many days as my son is weeks, and my grandson is as many months as I am in years. My grandson, my son and I together are 160 years. Can you tell me my age in years?"

#41770 Jokes » Mathematicians are Funny! » 2005-09-09 19:33:24

Jai Ganesh
Replies: 0

Fermat's Last Theorem

Like most mathematicians, Pierre de Fermat studied many problems for his own amusement. Indeed, many of his most important contributions were initially scribbled in the margins of books or in notes to friends.
One day in 1637, he made a curious note in his copy of Diophantus's Arithmetic: "The equation x^n + y^n = z^n, where x, y, and z are positive integers, has no solution if n is greater than 2... I have discovered a most remarkable proof, but this margin is too narrow to contain it."



Georg Cantor

Between bouts of insanity and frequent hospitalizations, Georg Cantor laid the foundations of set theory and the study of infinity. In 1878, the young mathematician discovered that there are in fact as many points on the minutest line segment as exist in all of space. Cantor, too, was incredulous. "I see it," he wrote to a colleague, "but I don't believe it!"



Peter Dirichlet

Such was his admiration of Karl Friedrich Gauss that the German mathematician Peter Dirichlet is said to have slept with Gauss's Disquisitiones Arithmeticae under his pillow.



Srinivasa Ramanujan: 1729

Srinivasa Ramanujan was a mathematical prodigy. "I remember once going to see him when he was lying ill at Putney," the mathematician G. H. Hardy once remarked. "I had ridden in taxicab number 1729, and remarked that the number seemed to me rather a dull one, and that I hoped it was not an unfavorable omen.
"'No,' he replied, 'it is a very interesting number; it is the smallest number expressible as the sum of two cubes in two different ways.'"



Paul Erdos : 2½ Billion year old


Paul Erdos :"In 1970, I preached in Los Angeles on `my first two and a half billion years in mathematics.' When I was a child, the Earth was said to be two billion years old. Now scientists say it's four and a half billion. So that makes me two and a half billion. The students at the lecture drew a timeline that showed me riding a dinosaur. I was asked, `How were the dinosaurs?' Later, the right answer occurred to me: `You know, I don't remember, because an old man only remembers the very early years, and the dinosaurs were born yesterday, only a hundred million years ago.'"

#41771 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-09 18:03:26

Problem # k + 21

If the diagonal and the area of a rectangle are 25 m and 168 m², what is the length of the rectangle?

#41772 Re: Maths Is Fun - Suggestions and Comments » hide buttons work when logged in » 2005-09-08 22:58:48

Yes, that would be fine! When the question or problem is no longer current, the hide tag would show the solution! Good thought smile

#41773 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-08 21:22:32

Problem # k + 20


What is the least number that should be multiplied to 100! to make it perfectly divisible by 3^50?

#41774 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-09-08 16:58:33

Problem # k + 19


At his usual rowing rate, Rahul can travel 12 miles downstream
in a certain river in six hours less than it takes him to travel the same
distance upstream. But if he could double his usual rowing rate for his 24
mile round trip, the downstream 12 miles would then take only one hour
less than the upstream 12 miles. What is the speed of the current in miles
per hour?

#41775 Re: Maths Teaching Resources » hehehe » 2005-09-08 16:19:36

kylekatarn wrote:

... but in the end...he didn't pass the exam and I felt a little guilty : (

During 1999-2000, I was teaching a student iin her Pre-University four subjects....Mathematics, Physics, Chemistry and English...French and Computer Science she learnt by herself...She passed in all subjects other than Mathematics...initially I felt guilty, because I knew Mathematics was the weakest link...but I didn't give up....I taught her Mathematics for two more years, she finished her Bachelor of Computer Applications and is now doing her MBA in London! I had to learn Digital Logic Fundamentals and Accountancy to teach her for her BCA, now I am delighted!
Sometimes, you teach and the student doesn't perform well.....are the teachers to blame? I'd say No..... smile

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