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## #1 Help Me ! » quadratic polynomial » 2015-04-24 23:18:27

niharika_kumar
Replies: 2

Let P(x) be a quadratic polynomial with real coefficients such that for all real x the relation 2(1+P(x))=P(x-1)+P(x+1) holds.
P(0)=8 and P(2)=32.
If the range of P(x) is [m,∞), then the value of m is?

## #2 Re: Help Me ! » permutation and combination » 2015-04-21 14:40:14

oh yes.

I've found it is usually a good thing to agree with bobbym.

## #3 Re: Help Me ! » permutation and combination » 2015-04-21 00:54:37

But the ways in which SS and SSS will come together will also include the cases when CC are not together.

## #4 Re: Help Me ! » permutation and combination » 2015-04-20 20:59:06

Question.
Find the number of 7 letter words that can be formed using the letters of the word SUCCESS so that the two C are together but no two S are together?

## #5 Re: Help Me ! » conics » 2015-04-17 03:16:36

thanks bob.

and yes I will surely be disturbing you with other problems on conic section as well.:)

## #6 Re: Help Me ! » conics » 2015-04-13 15:26:52

#3 normals to a parabola y^2 =4ax meet at (h,k).Then show that h>4a.

The question I have tried:-
#Find the locus of point such that 2 of the 3 normals drawn from them to the parabola coincide.
This is what i tried;

Now what to do after this.

This is what I don't know where to start.
#Find the locus of the vertices of the family of parabolas

## #7 Re: Help Me ! » conics » 2015-04-11 01:08:02

thanks bob as you really tried hard.But agnishom is right.I certainly know the basics but get stuck when the problems demand applications of many properties.One of the examples of such problem was the first one that I asked in this thread.

## #8 Re: Help Me ! » conics » 2015-04-10 17:21:19

I  meant conic sections.
my query was that how can I analyze the problems based on conic sections efficiently?

## #9 Re: Help Me ! » conics » 2015-04-10 03:33:10

oh thanks.

Well, I would be happy if you will help me by suggesting some ways on how to have a good command in conics. Pls help.

## #10 Re: Help Me ! » conics » 2015-04-05 23:09:38

Let

be squares such that for each n≥ 1, the length of a side of
equals the length of a diagonal of
.If the length of the side of
is 10 cm, then for which of the following values of n is the area of
less than 1 sq. cm.

## #11 Re: Help Me ! » conics » 2015-03-31 15:33:35

thank you for the detailed solution.

## #12 Help Me ! » conics » 2015-03-25 18:27:15

niharika_kumar
Replies: 22

The tangent and normal at the point P(at²,2at) to the parabola y²=4ax meet the x-axis in T and G respectively, then find the angle at which the tangent at P to the parabola is inclined to tangent at p to the circle through P,T,G.

## #13 Re: Help Me ! » permutation and combination » 2015-03-14 04:23:12

thanks I got it too.

## #14 Help Me ! » permutation and combination » 2015-03-12 16:35:57

niharika_kumar
Replies: 17

Consider the set of eight vectors V={

}.
Three non-coplanarvectors can be chosen from V in
ways.Then p is?

## #15 Re: Help Me ! » circle » 2015-03-05 15:15:11

can you give me a diagram of the double ordinate of a parabola.
I am not able to visualize it.

## #16 Re: Help Me ! » circle » 2015-03-05 15:13:55

thanks.

and
HAPPY HOLI to all of you.

## #17 Help Me ! » circle » 2015-03-04 18:56:29

niharika_kumar
Replies: 12

If two distinct chords of a circle

drawn from a point (p,q) is bisected by x-axis ,then which of the following is correct.

a)

b)

c)

d)

## #19 Re: Help Me ! » find minimum percentage » 2014-12-31 02:15:59

well there was a solution too which he gave.
But that solution is not being digested by me.
And the solution said that convert the percentage to the opposite of what it said. for example: If 70% have lost their left hand then there are 30% who have not lost it.And do the same with others.Then he added all these data claiming that maximum percentage who didn't loose any part is 90% ,hence minimum percentage who lost all parts is 100-90=10%.

When I asked him if the data would have been given like 50% each,he told me there won't be such question.

help.

## #20 Help Me ! » find minimum percentage » 2014-12-30 03:12:30

niharika_kumar
Replies: 6

hi friends.
I am back after few months. Feeling really good to be here again.
How are you all?

So here is my question.

In second world war 70% soldiers lost their left arm, 75% lost their right arm, 80% lost their left eye and 85% lost their right eye.
Find the minimum percent who lost all four parts?

pls help.

Niharika Kumar

## #21 Re: Help Me ! » Find the value » 2014-11-17 03:20:01

thank you so much bob

## #22 Re: Help Me ! » Find the value » 2014-11-15 15:48:06

anyhow, manually.

Did you appear in KVPY @agnishom.

## #23 Help Me ! » Find the value » 2014-11-15 15:40:11

niharika_kumar
Replies: 38

Find the value of

## #24 Re: Science HQ » collision » 2014-10-21 15:11:47

thank you so much bob.

## #25 Re: Science HQ » collision » 2014-10-18 22:42:27

bob bundy wrote:

Now for the horizontal motion.  At impact with the block, the velocity is still V and the block is moving at -V/4.  We aren't told the mass of the block so no momentum equation is possible.  But we can use the elasticity equation.  We'll have to assume e=1  again as we aren't told anything else.  So

You'll need to be careful with negatives here, but you should be able to get the velocity of the ball after the impact (assume block is still -v/4).

Bob

I am not sure if I could understand the way of using that equation properly.

Will you pls show how you placed all the terms in that.