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#43726 Re: Jai Ganesh's Puzzles » Problems and Solutions » 2005-07-29 19:54:39

Two candles A and B, of equal height but different circumferences, burn for 4 hours and 3 hours respectively. If the two are lit at the same time, after what time would one candle be half the height of the other? smile

#43727 Re: Help Me ! » Hi » 2005-07-29 18:22:15

Nora can paint 1/6 of a house in 1 day.
Therfore, she takes 6 days to paint the house.
Meera can paint the whole house 2 days faster.
So, she can paint the house in 4 days.
In one day, Meera can paint 1/4 of the house.
If both of them paint the house together, in one day,
they can paint (1/6+1/4) of th house. That is,
10/24 or 5/12. Therefore, the whole house can be painted
by them in 12/5 days, that is 2 2/5 days. smile

#43728 Re: This is Cool » the philosophy and science behind teleportation » 2005-07-28 18:27:54

We are discussing this 2.500 years ahead of mankind roll
Maybe in 4,500 AD, brain and the body could be digitized,
maybe then the DNA pattern would be
010100101011100101011001011100011010100010110001.........................
and not
AGCTGGCTAACGTTACTGTTACACGTACGGAATCAGTTAAGCTAAGCT..........

#43729 Re: Dark Discussions at Cafe Infinity » do fish have a personality » 2005-07-28 16:51:29

thinkdesigns wrote:

i don't think fish have real process of their mind, it is proven that they don't feel pain.

It is wrong to assume fish don't feel pain. Any member of the animal kingdom that reacts to touch does feel pain (I think smile)

#43730 Re: This is Cool » will tehre ever be a single particle that makes EVERYTHING » 2005-07-28 16:36:40

thinkdesigns wrote:

......or will it just keep getting smaller, if we do we will have gotten to the smallest possible thing,.....

Atoms were considered to be the building blocks, then the subatomic particles were discovered....and now, it is said that the subatomic particles like neutrons, protons, electorns etc are made up of quarks;
but I am not sure whether that is true for neutrinos, mesons, muons, positrons etc. roll

#43731 Re: Help Me ! » Relation between: inv, arc, co, arcco?? » 2005-07-28 16:31:30

That is neatly explained.
Both Sin-¹x and Arcsin x are one and the same, and both are in use in Mathematics Textbooks.
To make things simple, if Sin x = 1/2,
it follows that                  Sin -¹(1/2) = x
or                                 ArcSin(1/2)  = x

#43732 Re: Dark Discussions at Cafe Infinity » Serious Discussion! » 2005-07-27 00:09:01

An eye for an eye, a tooth for a tooth....
Extrapolated,
a life for a life roll
It takes the society nowhere.
But what do we do with criminals involved in
Homicide / Terrorism / Drug trafficking / Adultery / Molesting ?
Forgive them?
Award a lesser sentence like life imprisonment??
Banish them ??? roll

#43733 Re: Help Me ! » Integration... » 2005-07-27 00:01:50

GurraTedden wrote:

dx=asin(y)dt

(a is a constant value)

where y=y(t)

∫dx = ∫ asinyt dt
∫dx = a ∫sinyt dt

x = a(-cosyt/y) + Constant ??????????? roll

#43734 Re: Guestbook » maths » 2005-07-26 23:03:07

shelly wrote:

what is your name
from shelly

Hi Shelly,
There are 909 registered users in this forum.

#43735 Re: This is Cool » One divided by Infinity » 2005-07-25 20:32:22

The logic seems acceptable.
It is easy to say 1/∞ is 0 because 1/0 is ∞,
just as 1/(a/b) = b/a.
If 1/a=b, it follows that 1/b=a smile
Indeterminate forms are only when both a and b are equal to zero,
or both a and b are equal to infinity.
Abishek, you missed another indeterminate form.
That is 0^0 smile

#43736 Re: Help Me ! » . » 2005-07-25 19:33:58

The binomial expansion of the Left Hand Side
contains two terms, among many, which are
a^a*n and b^a*n which appear to make the LHS greater than the RHS,
but when we assign arbitrary values,
say a=10, b=1,000,000,000 and n=100
the LHS is (1,000,000,010)^1000, which would contain 9,001 digits;
the RHS becomes
100 x (100^1,000,000,000) which would contain more than 2 billion digits!
This happened because we assumed b>>n.
Otherwise, the LHS may be greater.
Say, when a=10, b=100, n=1000.
LHS would be 110^10,000 containing 20,414 digits and the RHS would be much smaller, viz. 100*(1000^100), containing approximately 300 digits! smile

#43737 Re: Help Me ! » As easy as it seems? » 2005-07-25 16:29:36

You may also remember, given the roots of a quadratic equation, the equation can be got thus:-

x² -(Sum of the roots)x + (products of the root) = 0

#43738 Re: Help Me ! » Substitution Method (where two lines cross) » 2005-07-25 16:26:05

Solving the two equations, you get
x = -5/2, y = -1/6
Hence, the two lines cross at
(-5/2, -1/6)

How the two equations are solved:-
First equation can be written as                x+3y = -3
The second equation can be written as     x - 3y = -2
Adding the two, we get                           2x = -5, or x = -5/2
Substituting this value in equation (1)     -5/2 + 3y = -3
                                                                       3y = -3 + 5/2
                                                                       3y = -1/2
                                                                         y = -1/6

#43739 Re: This is Cool » Which of the two is greater? » 2005-07-25 16:20:06

kylekatarn wrote:

it seems that yCritical "slowly"(?) approaches the limit of 1 as x approaches +oo

looking forward to hear comments on this topic!

Yes, you are correct! ycritical approaches 1, but is certainly greater than 1, as x approaches + ∞

#43740 Re: Dark Discussions at Cafe Infinity » Wink Murder 2 » 2005-07-25 16:15:49

I got killed when I was riding a bike, and I was shot at a short range with a pistol in the head sad

#43741 Re: Jokes » Mnemonics » 2005-07-22 22:54:44

Don't ever try to derive a mnemonic for pi.......
That would be a useless exercise.... sad

#43742 Re: Jokes » Mnemonics » 2005-07-22 22:37:48

The world record holder remembers 100,000 places smile

#43743 Introductions » Enough is enough! » 2005-07-22 22:35:41

Jai Ganesh
Replies: 11

Okay, I shall tell you who I am!
I am J Ganesh, who forgot thinking after 15 years of age.....
I think more like the Britons than they do,
I am simply JG or Socrates Ganesh...
and my idol is the greatest mathematician ever....
Niels Henrik Abel....
smile

#43744 Re: Help Me ! » Im beginning to think this is impossible.... » 2005-07-22 22:29:02

Thanks, Mathsisfun,
I am on the verge of post # 200
and this an occassion for me to celebrate,
I shall take a big chunk of thhat big_smile

#43745 Re: This is Cool » Which of the two is greater? » 2005-07-22 22:25:51

Mathsy, I think you missed this post!
With all the available technology, you could have well improved upon those digits! smile

#43746 Jokes » Mnemonics » 2005-07-22 22:17:32

Jai Ganesh
Replies: 14

To
express
e
remember
to
memorize
a
sentence
to
simplify
this.
Can you think of mnemonics for pi?

#43747 Re: Introductions » hi » 2005-07-22 22:12:29

Oh I am tired of this......................
TRUCE..............at 140 Decibels.....:)

#43748 Re: Dark Discussions at Cafe Infinity » Be aware of my absence » 2005-07-22 22:08:45

We would be missing you all......
Do join us at the earliest........ smile

#43749 Re: Maths Teaching Resources » Maths-Whizz - Brilliant resource » 2005-07-22 22:06:40

mathematics is for all of us,
the poorer are always trhe better,
my Guru is Niels Henrik Abel, born in Norway smile

#43750 Re: Maths Teaching Resources » is maths hard? » 2005-07-22 22:04:03

MaTHEMATICS IS THE HIGHEST DEGREE OF LOGIC
AND IF YOU THINK RIGHT, MATHEMATICS IS WITH YOU smile

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