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## #1 Re: Help Me ! » Maths » 2009-06-12 01:01:30

nothin can be said

## #2 Re: Help Me ! » Area and Volume » 2009-06-10 15:26:29

hehe no ..............

ty

## #4 Re: This is Cool » A man sent into the future » 2009-06-10 01:03:44

I didnt get the meaning of ahead of himself... can u enlighten further dark light

## #5 Re: Help Me ! » Area and Volume » 2009-06-10 01:02:34

whosoever asked you to search this thing tell the same reply I gave...

## #6 Re: Help Me ! » Area and Volume » 2009-06-10 01:01:29

it is meaningless pal... there is nothin like this defined

## #7 Re: Help Me ! » Area and Volume » 2009-06-10 00:58:01

hey the volume is not defined for rectangles, squares, circles as these are 2 dimensional figures ... it is for 3 dimensional figures ...................

so u cannot say anything on this

there is nothing like the volume of the square, .....

## #8 Re: Help Me ! » Area and Volume » 2009-06-10 00:47:51

hey solomon

i didn get the question ....

the volume is 3d and area is for a 2d plane........... so wat xactly u asking?

rofl!!!

## #10 Re: Formulas » Logarithm Formulas » 2009-06-09 21:04:36

ganesh wrote:

If

then

because

hey ganesh jus a little thing
if we take  A and B of the same signs

here it should be

..

and in the other ones also... the argument has to be alwys positive

## #11 Introductions » Hello Every1!! » 2009-06-09 20:55:59

noobard
Replies: 3

Hey i am a big lover of mathematics, if u keep calculus apart ..(ee gets on the nerves)... and m preparing for one of the toughest management entrance exam called CAT ( if u hrd abt it)..... and on this forum i found some pretty interesting stuff which are pretty helpful and hv developed an additional interest to scratch out more on my own...

I missed cracking Maths olympiad by a mark .......... but I am very keen to learn and I hope i hav found the right place and right people..'.

Cheers

NoobarD

## #12 Re: This is Cool » 0^0 » 2009-06-09 20:47:04

JaneFairfax wrote:

Hw?

## #13 Re: This is Cool » 7*11*13!!! » 2009-06-09 20:45:34

DarkLightA wrote:

Any number with an even number of digits that is a palindrome (same forwards and backwards, like 529925) is a multiple of 11.

nice.. can be proved by divisibility rule for 11

nice one !!!!

## #15 Help Me ! » equations in binary » 2009-06-09 00:22:10

noobard
Replies: 2

Hey jus help me with this thing

Suppose ax+by=d and ex+fy=g are two equations in binary (base 2)..........with a,b,c,d,e,f,g being in binary (obviously)....so hw to solve it directly rather then converting to the conventional decimal and getting the answer later converting it to binary.

can it be generalised for any other base??

## #16 Re: Help Me ! » help got a test in 2 days and i am studying math after 30 years » 2009-06-09 00:16:25

The method describe by mathys... is fine...we get a total of 39 credits earned by the guy out of 52 (maximum)...dividing 39/52 gives gives 0.75 ..... for 10 scale it becomes 7.5 and for 4 scale it will be 4*0.75 which is 3....................it is lik if a guy gets 7.5 out of 10 wat will he get out of 4...........

## #17 Re: Help Me ! » factoring polynomias » 2009-06-08 21:41:50

ll tell u a simpler way
wen it comes to factorising polynomials
think first of a^2-b^2=(a+b)(a-b)
so keep 16y^2 aside for a while ....
and we can see that 25x^2 -10x+1 is a perfect square of 5x-1
so the problem is now 16y^2-(5x-1)^2which is nothin but
(4y-5x+1)(4y+5x-1)

;)

## #18 Re: Help Me ! » fractions/LCM/GCM » 2009-06-08 21:27:49

is the answer 43*47*15...... ???the credits...
the question is still unclear but the lcm of 43*5 and 47*3 will give the answer 43*47*15 which gives the minimum number of equal credits and the equal number of years spent in the college doesn matter

## #19 Re: Help Me ! » combination and permutation problem » 2009-06-08 21:13:05

i also got 50...
but ma method is a bit different

as i said earlier we got 120 triangles ....now we subtract the cases we we hav 2 adjacent and three adjacent and hence we get the answer...so for two adjacent ....we choose two adjacent triangles ...which can be in 10 ways and the third one has to be chosen from the remaining 6(10-(two chosen and two neighbours of them)..so 10*6 hence 60
and no of groups having all the three bunched is 10

so 120-60-10
which is nothin but 50

## #20 Re: Help Me ! » Tangent to circle » 2009-06-08 20:36:01

this can be easily solved by co ordinate geometry

the equation is a circle with center at origin................radius 6
and y=k is a line parallel to the x axis....
making the graph we can clearly see that it will be tangent only at (0,6) and (0,-6).........so k can be +6,-6
...if u dun like this way .....the perpendicular distance from the center of the circle to the tangent is equal to radius....so if y=k is a tangent then (modulus)k =6
which gives the same thing

## #21 Re: This is Cool » 7*11*13!!! » 2009-06-08 20:30:57

zzzzzzzzzz ganesh i thought being a new bee on this forum so started of with this ...........nice u told me that ....  :-|

## #22 This is Cool » 7*11*13!!! » 2009-06-08 16:40:37

noobard
Replies: 7

We most of the times think that 1001 is a prime ...well it is not
it is a product of 7,11,13
so wen we see a 6 digit number abcabc then it is nothing but 1001*abc...and can be split into factors 7*11*13*factors of abc...
and hence can be analysed further

kp
enjoyin maths

## #23 Re: This is Cool » Prime Numbers!!! » 2009-06-08 15:46:24

ya bobbym ... true as u say.............................

The factorial becomes sad for large numbers...that is why i wrote this algorithm is for the programmers ......and i found this pretty amusing when i saw a question quoted as
If n is a number such that  (n-1)!+1 is divisible by n...Find the number of n (between 1-100) satisfying this ............so the answer was at hand 25 ....;)

## #24 Re: Help Me ! » Number of Factors. » 2009-06-08 15:41:57

oops i wrote it for the first part....zzzzzzzzzz

ll try ma way for the second part............

## #25 Re: Help Me ! » combination and permutation problem » 2009-06-07 22:35:15

we can eliminate the options ...
The maximum choices will be 10c3...which is nothin but 120
so C and D are out of the picture...........It cannot be 120 also because we have our restrictions...
So we a re left with 112 and none of these............ll try figuring out the xact answer