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#43476 Re: Guestbook » boo hoo » 2005-10-28 16:01:48
You are wrong, Tiger. I like you. 
#43477 Re: Help Me ! » Perpendicular Vectors and Scalars » 2005-10-27 21:32:13
Senor, correct me if I am wrong.
(And it is senior.)
That was intentional.
Abbr. Sr.
Used as a courtesy title before the surname, full name, or professional title of a man in a Spanish-speaking area.
Used as a form of polite address for a man in a Spanish-speaking area.
(Spanish)
#43478 Re: Help Me ! » Intersecting Planes » 2005-10-27 19:35:59
This page may be of some help.
This example may also be referred, if necessary.
#43479 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-27 16:48:06
Problem # k + 41
Prove that the number 512³ + 675³ + 720³ is not prime.
#43480 Re: Help Me ! » Steradian » 2005-10-27 15:54:04
A unit of measure equal to the solid angle subtended at the center of a sphere by an area on the surface of the sphere that is equal to the radius squared: The total solid angle of a sphere is 4π (4 pi)steradians.
The unit of solid angle adopted under the System International d'Unites.
#43481 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-27 15:47:43
Well done, Mathsy!
#43482 Re: Help Me ! » Perpendicular Vectors and Scalars » 2005-10-27 15:33:39
I apologize. I am not supposed to comment on Mathsyperson's and Insomnia's replies and believe me, we are polite and have a strict code of conduct in this forum and no deviation is tolerated.
Insomnia, the new moderator : Please note.
Mathsyperson, my senior in this forum : Senor, correct me if I am wrong.
#43483 Re: Jokes » Clean Jokes » 2005-10-26 21:41:31
Why do we press harder on a remote control when we know the batteries are getting weak?
Why do banks charge a fee on "insufficient funds" when they know there is not enough?
Why does someone believe you when you say there are four billion stars, but check when you say the paint is wet?
Why doesn't glue stick to the bottle?
Why do they use sterilized needles for death by lethal injection?
Why doesn't Tarzan have a beard?
Why does Superman stop bullets with his chest, but ducks when you throw a revolver at him?
Whose idea was it to put an "S" in the word "lisp"?
If people evolved from apes, why are there still apes?
Why is it that no matter what color bubble bath you use the bubbles are always white?
The statistics on sanity are that one out of every four persons is suffering from some sort of mental illness. Think of your three best friends, if they are okay, then...
#43484 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-26 20:38:05
Problem # k + 40
How many are we?
You tell us the answer, knowing that the probability that at least two of us have birthdays on the same day is less than half, but that this would not be the case were we one more in number.
#43485 Re: Introductions » good day » 2005-10-25 16:28:37
I am Ganesh, from Chennai, India, one of the Moderators.
#43486 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-25 16:22:16
Problem # k + 39
Of all the five digit numbers, how many are odd and without repetition of digits?
#43487 Re: Jokes » Clean Jokes » 2005-10-25 16:12:34
Hi m_f,
Welcome to the forum.
Nice pic.
#43488 Re: This is Cool » Really good at Mathematics? » 2005-10-25 16:11:05
Nobel prize is not awarded for Mathematics. Field's Medal is the Nobel Prize equivalent in Mathematics. However, its awarded only once in four years.
#43489 Re: Help Me ! » Taylor Series Expansion » 2005-10-25 16:09:33
sin(x) = sin(0) + xcos(0) −x²sin(0)/2! − x³ cos(0)/3!
+ x^4 sin(0)/4! - x^5 cos(0)/5! + ...............
= x - x³/3! + x^5/5! - x^7/7!................
#43490 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-24 16:14:55
Problem # k + 38
Prove that, for any natural number n ≥ 2, there exists atleast one prime number between n and 2n.
#43491 Re: Help Me ! » geometry » 2005-10-24 16:13:22
C)in assemble N ,every number is white or black so that white + black=black
prove : white + white = white
Let white=0, black=1;
white + black = 0 + 1 = 1 = black
white + white = 0 + 0 = 0 = white, Proved!
For A), B) please give some time. Yes, Proofs aren't too easy. They are time consuming.
#43492 This is Cool » Really good at Mathematics? » 2005-10-23 20:49:23
- Jai Ganesh
- Replies: 7
Are you very good at Mathematics? This is the award you should aspire for, and get, before you are forty.
For more information click here.
#43493 Re: Help Me ! » basic geometry... » 2005-10-23 20:32:12
This page would be of help.
A linear equation has to necessarily be of degree 1. (degree of a polynomia or an equation is the highest power of any varibale)
#43494 Re: Help Me ! » Prove that 2n natural numbers is n(2n+1) » 2005-10-23 16:09:46
I only started a level is there a easier way? I think I saw "S=n/2[2a + (n-1)d]" when the teacher did it.
You can think of a sum of n natural numbers as an Arithmetic Progression and use this formula.
S = n/2[2a + (n-1)d]
Here, n = n, a = 1, d = 1
Therefore, S = n/2[2 + (n-1)1]
S = n(n+1)/2
#43495 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-22 18:39:03
Problem # k + 37
A string of 1996 digits begins with the number 6. Any number formed by two consecutive digits is divisible by 17 or 23. The number contains two consecutive digits which are multiples of 17 and multiples of 23. What is the last digit?
#43496 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-22 18:35:03
#43497 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-21 23:39:25
Problem # k + 36
Is it true that n^3+5n-1 is prime for any natural n?
#43498 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-21 23:09:16
Problem # k + 35
An easy one:-
Dazzy fishes for more than a week. He experiences three different levels of success. On a good day he catches 9 fishes. On a bad day he catches only 5 fishes. On other days he catches 7 fishes.
In all, Dazzy catches 53 fishes. How many bad days did he have?
#43499 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-10-21 22:52:24
Thats correct, Mathsy!
#43500 Re: Puzzles and Games » Math Equation Mind Bender » 2005-10-21 22:37:08
I tried many combinations, finally got it. I first drew the conclusion that 3/4 should figure in the denominator. Thereafter, it was juggling with numbers.
I think the problem has a unique solution. Mathsy beat me, but I should say, it didn't take more than 10 minutes! (There was a gap of more than 90 minutes between my first and second periods of five minutes)