# INMO 2019 Discussion

This is the place where we may discuss various problems and get updates of INMO 19. I expect the students of different states to post some problems discussed in their INMOTC. I will regularly upload some problems and even practice tests for INMO and expect you to do so too. Hope we all do perform well in INMO and many of us may even get selected for INMO IN MY NEXT POST, I WILL SEND A MOCK TEST A BIT EASIER THAN INMO, AS IT IS JUST THE BEGINNING.

Note by Maalav Mehta
2 years, 4 months ago

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Inmo provisional scores are out!!

- 2 years, 2 months ago

What is your score? Mine is 16, Samip 19, Pritesh 29, tanishka 14 are the scores I know till now from GUJARAT

- 2 years, 2 months ago

My scores look messed up. I could solve P1 and P2 and attempted P6 (almost pseudo proved it), but I got only 7. If there are 5 marks for attempting P6, then I was given only 2 marks for 2 correct questions. What the hell!

- 2 years, 2 months ago

P6 deserved to be deleted. Anyway, better to file RTI to get the truth about evaluation.

- 2 years, 2 months ago

I do agree. I made assumptions in P6 due to lack of options. Anyways, though I felt Functional Equations was my stronghold and I wasted a lot of time in that question, my best wishes to all who did really well. Hope India succeeds this time at IMO.

- 2 years, 2 months ago

I am Param Kansara and I got 26 from Gujarat

- 2 years, 2 months ago

Who is pritesh

- 2 years, 2 months ago

My friend from class 9. He studies at Allen

- 2 years, 2 months ago

Congrats, you got slected for INMO this year also. 23marks is impressive

- 1 year, 5 months ago

1st Indian National Mathematical Olympiad MOCK 2019 Time: 4 hours Instructions: • Calculators (in any form) and protractors are not allowed. • Rulers and compasses are allowed. • All questions carry equal marks. Maximum marks: 102.

1.A circle passes through the vertex C of a rectangle ABCD and touches its sides AB and AD at M and N respectively If the distance from C to the line segment MN is 5 units, find the area of ABCD.
2.Consider the set {3,5,7,9}. You can choose any 2 numbers a,b and replace them by (4a+3b)/5 and (3a-4b)/5. Prove that you can never get the set {2,3,4,9}.
3.A 3*3 square is said to be a mystic square if i)Its entries are from 1 to 13(both inclusive, repetition allowed) ii)The sum of any row, column or diagonal is always divisible by 13. Find the number of MYSTIC SQUARES.
4.In a triangle ABC, AB=AC and angle A is 20 degrees.D is chosen on AC such that AD=BC.Without using trigonometry, find angle ABD.
5.Let P(x) be a cubic polynomial function with positive coefficients..Prove, if -1≤P(x)≤1 for all x such that -1≤x≤1, prove that sum of coefficients of P(x) is at most 7.
6.Find all functions f:R to R which obey
f((x-y)²)=f(x)²-2xf(y)+f(y)²

- 2 years, 4 months ago

Thanks for the mock test!!! What are you focusing on preparing??? Geometry??

- 2 years, 4 months ago

I want to improve at geometry, but I hate doing it.

- 2 years, 4 months ago

Well, you can start off with some problem solving on AOPS..........BUT, if u want to learn new stuff, the wikis on Brilliant are REALLY good ones...........

- 2 years, 4 months ago

Also, if u hate doing it, then focus on something which you like doing and prepare that.......:)

- 2 years, 4 months ago

Which state are you from?

- 2 years, 4 months ago

I am from Noida..........(UP region).....You???

- 2 years, 4 months ago

Gujarat

- 2 years, 4 months ago

When is your INMOTC and which teachers are coming?

- 2 years, 4 months ago

WHOAH!!!! You have an INMOTC???!!! That is great dude.........yahan pe to aisa kuch inform nhi kara hai!! lol............

- 2 years, 4 months ago

You may ask your coordinator to arrange some camp or you may enquire in neighbouring states if they allow outside students

- 2 years, 4 months ago

All the best for tomorrow

- 2 years, 3 months ago

Thanks!!!! Same to you!!

- 2 years, 3 months ago

What about the last question in INMO 2019? Since the question was faulty, how will the marking be made?

- 2 years, 3 months ago

Should simply be ignored and marks be awarded to none.

- 2 years, 3 months ago

But that is not correct as many would have spent hours on the problem as no one would have expected it to be incorrect. On the other hand, many wouldn't even have tried the question. It is unfair that both get 0 marks

- 2 years, 3 months ago

i feel that someone who has tried to draw logical steps from the given statements in the problem should be awarded marks. Someone who forcibly tries to prove the false statement to be true must not be awarded marks. I really doubt if someone actually tied to disprove it.

- 2 years, 3 months ago

Let us post our scores Mine is 34

- 2 years, 2 months ago

my score is 54

- 2 years, 2 months ago

You will get selected for sure

- 2 years, 2 months ago

but last to last year the cutoff was around 60

- 2 years, 2 months ago

But this time it is not so. Check out aops

- 2 years, 2 months ago

It was 47

- 2 years, 2 months ago

Congratulations man!

- 2 years, 2 months ago

thanks!

- 2 years, 2 months ago

Which region are you from?

- 2 years, 2 months ago

maharashtra goa

- 2 years, 2 months ago

pune

- 2 years, 2 months ago

Were you merit holder, because in the lost I can't find someone from Maharashtra having 54 marks. There is one with 58 though

- 2 years, 2 months ago

yes

- 2 years, 2 months ago

What is 'lost'

- 2 years, 2 months ago

sorry, I wanted to write list

- 2 years, 2 months ago

Which list?

- 2 years, 2 months ago

It is on aops

- 2 years, 2 months ago

But where?

- 2 years, 2 months ago

https://artofproblemsolving.com/community/c260h1781370 See the first post

- 2 years, 2 months ago

Thanks, what is your name in aops

- 2 years, 2 months ago

Math-Wiz

- 2 years, 2 months ago

Final scores are out. When do you expect the list will be revealed?

- 2 years, 2 months ago

What should be the merit cut off?

- 2 years, 2 months ago

I have no idea. 30-50 somewhere

- 2 years, 2 months ago

40

- 2 years, 2 months ago

Find all functions f:R→R satisfying the equation f(f(x)) + f(x) = 6x

- 2 years, 4 months ago

ALL THE BEST FOR TOMORROW GUYS AND GIRLS!!!!!!!!!!!

- 2 years, 3 months ago

Same to you!!!!

- 2 years, 3 months ago

How did it go????? How many could you solve????

- 2 years, 3 months ago

None

- 2 years, 3 months ago

Really?

- 2 years, 3 months ago

Yes

- 2 years, 3 months ago

What do you expect from a class 9 student?

- 2 years, 3 months ago

Do you think that the cut off may be lower this time since as per my experience this year, the paper was relatively tougher

- 2 years, 3 months ago

Yes, the cutoff will be around 35-40

- 2 years, 3 months ago

Greater than 42..check out AOPS

- 2 years, 2 months ago

What is your score? Any chances of selection?

- 2 years, 2 months ago

No...I didn't do well...In Odisha highest score is 39 by Aatman...Most got single digit scores.however from the checking it is clear that if even a single step is wrong or a claim too you end up with a zero in that question

- 2 years, 2 months ago

Even in Gujarat the highest score is 29 as known till now(no idea about merit holders). So, no chances of selection in Gujarat

- 2 years, 2 months ago

Hey everyone. I appeared for INMO 2019 and solved P2 and P3. In P6, I managed to provide a "pseudo-proof" that f(x,y) =1. What are my chances of selection? Also, I couldn't solve P1 but I heard many saying that it was the easiest problem. Is this really the case?

- 2 years, 3 months ago

Hey dude........same case over here...........I mean even I have done the EXACT same things except P6, in which I was only able to prove the first part..........Oh well.......Chances are slim...........And Yes, P1 was the easiest......IDK why it did not strike me during the exam........!!!!

- 2 years, 3 months ago

Can you provide a hint for P1?

- 2 years, 3 months ago

Well, Allen has already posted their solutions, but my method was using a lot of trigonometry...........You know, Sine rule and Cosine rule........and that took me too long.....

- 2 years, 3 months ago

Btw, which class are you in?? And from which state??

- 2 years, 3 months ago

I am in 12th class from Rajasthan state. What about you?

- 2 years, 3 months ago

Ohhh I am in class 11th.......Uttar Pradesh........

- 2 years, 3 months ago

So, you are giving JEE???

- 2 years, 3 months ago

Yep

- 2 years, 3 months ago

Did you hear that P6 was wrong? What would be impact. Will it be deleted or there could be a reexam??

- 2 years, 3 months ago

Check it on aops

- 2 years, 3 months ago

What do u think? HBCSE will delete the qn?

- 2 years, 3 months ago

Probably, but that is not correct as many would have spent hours on the question without knowing that it is incorrect

- 2 years, 3 months ago

What could be the cut off? I guess, it should be around 40-45.

- 2 years, 3 months ago

HBCSE has provided an update on their site: "In question number 6 of the INMO2019 held on 20th January, 2019, a hypothesis was unfortunately left out inadvertently. As a result, the problem was incomplete. A suitable resolution of the problem will be worked out in consultation with examiners and students’ efforts will be taken care of during the evaluation. — B. Sury, National Co-ordinator."

- 2 years, 3 months ago

Yup........maybe they'll mark it correct for everyone and thus increasing the cutoff........

- 2 years, 3 months ago

No they probably won't do that. I think they will give 0 for no attempt and provide some marks according to the attempt.

- 2 years, 3 months ago

I don't think that would be reasonable. If marks for attempt is to be awarded then it should for every question and not just for question 6.

- 2 years, 3 months ago

For p2 I did not use php but some approach that is explicitly not php but just the same thing as that. How much do I expect?

- 2 years, 3 months ago

If it is mathematically correct, you get full

- 2 years, 3 months ago

You don't have experience about change in checking methods

- 2 years, 2 months ago

@Suchir Kaustav @Maalav Mehta Is this the first time this has happened that a question in inmo came wrong? If this did happen before then what was done? Any idea?

- 2 years, 3 months ago

I remember it happened in 1999 and 2011. But no idea what was done

- 2 years, 3 months ago

Reexam is a huge logistical challenge on the part of HBCSE. I think they should increase the number of selections.

- 2 years, 3 months ago

Inmo 2019 cutoff

- 2 years, 2 months ago

Around 48

- 2 years, 2 months ago

Provisional cutoff ~50...may increase after re-evaluation...btw how many of u guys are expecting increase in ur score..plz post ur current score and expected score

- 2 years, 2 months ago

where did you find provisional cutoff

- 2 years, 2 months ago

Aops

- 2 years, 2 months ago

What should be the merit cut off?

- 2 years, 2 months ago

38

- 2 years, 2 months ago

What was the cut off then for IMOTC?

- 2 years, 2 months ago

Results declared. The cutoff is most probably 46

- 2 years, 2 months ago

Cool cool.

- 2 years, 2 months ago

What about Merit cut off? When will the merit list be declared?

- 2 years, 2 months ago

In August

- 2 years, 2 months ago

good comment

- 2 years ago

- 2 years ago

- 2 months, 4 weeks ago

How was the inmo?

- 2 years, 3 months ago

Tougher than ever, the fifth question used something called inversion(according to some AOPSers), which has not ever been asked in INMO. Could you solve P6?

- 2 years, 3 months ago

Yeah problem no 6 looked easy but solving it took me complete hour and mind bending brainstorming and I skipped two or three lemmas and messed everything but solved it. Seems they would care to give 2 or 3 marks.

- 2 years, 3 months ago

How did you solve it?

- 2 years, 3 months ago

No exotic methods just little brainstorming , some examples, inducing them ,predicting the power rule and then proved.😃

- 2 years, 3 months ago

Bro, the last question is incorrect and in the solution of Allen faculties, they have found a counter example

- 2 years, 3 months ago

Yes me too saw today my answer is as not Allen's solution buy I used the continuity of the function too. So seems wrong now.

- 2 years, 3 months ago

The power rule assumed by me was wrong as I thought only about rational numbers didn't seek for irrational ones.

- 2 years, 3 months ago

If the ans is wrong and the approach is correct or vice versa how much can one expect??

- 2 years, 3 months ago

If the approach is more than 70 percent correct, you may expect 12 marks. If the answer is correct but obtained by doing some nonsensical stuff, then you may get 2 or 3 marks

- 2 years, 3 months ago

If approach is more than 90% correct but you have even one fault then u get a zero

- 2 years, 2 months ago

What's going on? When will results be posted? Final scores are out, that should be no trouble now

- 2 years, 2 months ago

Results will be out on 5 march

- 2 years, 2 months ago

F

- 2 years, 2 months ago

Hey what can be expected cutoff this year??

- 2 years, 3 months ago

RMO coordinator of Gujarat told that according to trend, you are required to solve 3-4 questions

- 2 years, 3 months ago

This time I guess cutoff will be around 40

- 2 years, 3 months ago

What about cut off for merit certificate?

- 2 years, 3 months ago