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Catalogs Discussion Forums -> About IITs and JEE -> my eml rank is 13k What are my chances -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

I think you should probably consider repeating if you are sure of getting in the Merit List next year or else you would have been selected in other exams, haven't you?

Catalogs Discussion Forums -> Algebra -> IMO 1983 inequality -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

I don't know about substitution but I can prove it like this:

Let a^2 b = m , b^2 c = n and c^2 a = o; and a, b and c.

Without any loss of generality, let's assume that a <= b <= c ( as the expression is symmetrical )

Obviously, m <= n <= o.

Now the value of ma + nb + nc is greater than or equal to that of mb + nc + oa ( From the rearrangement inequality )

So a^3 b + b^3 c + c^3 a >= a^2 b^2 + b^2 c^2 + c^2 a^2, or a^3 b + b^3 c + c^3 a - a^2 b^2 - b^2 c^2 - c^2 a^2 >=0.

This is nothing but the expanded form of the given expression.

Hence Proved.

Catalogs Discussion Forums -> Algebra -> aieee question...just try if can find remainder when we divide 1! +2! + 3!...............+100! by -> Go to message
This Post 10 points    (Olaaa!! Perrrfect answer.   in 2 votes )   [?]

18 = 3^2 . 2

For the factorials greater than or equal to 6!, they are divisible by 18. So they leave no remainder.

For those before,

1! + 2! + 3! + 4! + 5! = 1 + 2 + 6 + 24 + 120 = 153.

153 / 18 leaves the remainder 9.

Catalogs Discussion Forums -> Thermal Physics -> if a gas of given volume at temp 250K is heated by 1K percentage increase in pressure is? -> Go to message
This Post 2 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

PV = nRT

delta P V = nR delta T.

divide the two

delta P / P = delta T / T.

So the percentage increase in pressure is the same as that in temperature = 1 / 250 * 100 = 0.4 %

Catalogs Discussion Forums -> Algebra -> If f(x)=x-[x] ,x is a non-zero real no., where [x] is the gretest integer function less than or -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

No Vishnu {1/x} is not equal to 1/{x}.

Catalogs Discussion Forums -> Physical Chemistry -> How do you solve these type of questions? -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

10 Volume H2O2 means that 1 Litre of this H2O2 liberates 10 Litres of O2 at STP.

So 500 cm^3 of O2 are liberated by 50 cm^3 = 50 mL of this H2O2.

Catalogs Discussion Forums -> Algebra -> votes and 10 salutes assured who does this:- if x and y be two rational numbers satisfy x^3+y^3=2xy -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

Sorry Kapil I don't think square root of a rational number is always rational. Take 3 for example. root(3) is irrational.

Catalogs Discussion Forums -> Optics -> there is a convex lens made up of glass.... on its one side there is water while on the other side i -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

Let the Radii of curvature be R1(air side) and R2(water side)

Then for rays coming from infinity, u = -infinity.

Apply the refraction formula

u2 / v - u1 / u = (u2 - u1) / R1

4/3v - 0 = 1/(3R1)

v = 4R1

Then for the second surface

3/2v - 4/(3(4R1)) = -(4/3 - 3/2)/R2

3 / 2v - 1/3R1 = 1/6R2

v = focal length

3 / 2f = 1/6R2 + 1/3R1

Catalogs Discussion Forums -> Algebra -> Guys,how to find the no of roots of a polynomial equation? Ok,if its strictly increasing I know h -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

Depends on the equation. What is the polynomial equation?

Catalogs Discussion Forums -> Analytical Geometry -> If a farmer can feed 4 cows for three weeks, then gets two more cows, how many weeks will the food -> Go to message
This Post 2 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

It's a unitary method question. If he can feed 4 cows for three weeks, he can feed a cow for 4*3 = 12 weeks.

So he can feed 6 cows for 12 / 6 = 2 weeks.

Catalogs Discussion Forums -> Games, Puzzles and Quizzes -> can someone tell me who has scored fastest century in one day cricket -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

I don't know this one, but wikipedia says Nathan Astle.

Catalogs Discussion Forums -> Games, Puzzles and Quizzes -> can someone tell me who has scored fastest century in one day cricket -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

I think it is Sir Don Bradman(officially approaching 100, unofficially > 100)

Catalogs Discussion Forums -> General Physics -> magnitude and direction of net force acting on drop of rain falling down with a constant speed -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

If the drop is falling down with constant speed, its linear momentum is not changing, and so no force is acting on it.

The gravitational force cancels the viscous and buoyant forces exactly and no force acts on the drop.

Magnitude - 0, direction - not defined.

Catalogs Discussion Forums -> Games, Puzzles and Quizzes -> can someone tell me who has scored fastest century in one day cricket -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

This is a recent one.... Rahul Dravid with 183 catches I think.

Catalogs Discussion Forums -> Organic Chemistry -> A typical compound undergoes Cannizzaro's reaction as well as Aldol condensation. The possible compo -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

Great answer Madhusudan sir. Only an expert with thorough knowledge of chemistry would have been able to answer the question.

Although I'll have to say that the question was out of JEE syllabus.

Catalogs Discussion Forums -> Games, Puzzles and Quizzes -> can someone tell me who has scored fastest century in one day cricket -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

I think 2, one of them was Anil Kumble.

Catalogs Discussion Forums -> Thermal Physics -> kinetic theory -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

The process will probably take place at constant volume, if it happens in a closed container.

So the molar heat capacities will be 3R for CO2 and 2.5R for O2

Let the final temperature be T.

Heat recieved by CO2 = Heat given by O2

3R(T-27)(22/44) = 2.5R(37-T)(16/32)

Solve it to get T = 31.55 degrees approx.

On the other hand, if it is given that the process takes place at constant pressure, then the heat capacities will be 4R for CO2 and 3.5R for O2.

4R(T-27)(22/44) = 3.5R(37-T)(16/32)

Solve to get T = 31.66 degrees approx.

Catalogs Discussion Forums -> Games, Puzzles and Quizzes -> can someone tell me who has scored fastest century in one day cricket -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

Viv Richards, off 56 balls.

Catalogs Discussion Forums -> Games, Puzzles and Quizzes -> can someone tell me who has scored fastest century in one day cricket -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

Shahid  Afridi in 37 balls in 1996 against Sri Lanka.

Catalogs Discussion Forums -> Algebra -> binomial coeff. ques. -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

No, if n = 10, the answer is 2^10.

 
 
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