# JEE-2018

Hello everybody, I'm just another $JEE$ aspirant out of the many at Brilliant , and with Due respect ,would really appreciate the accompany of fellow Brilliant members who are appearing for $JEE-2018$; to please Use this discussion platform for all JEE-releated queries and Questions discussions ; Also it would be a matter of great joy to seek help from the "Seniors", :) of course the IITians - 2017 ...would be really glad if they could help us , you guys are great source of inspiration for all of us , please do comment and guide your juniors, us. Also ,any Brilliant member, please comment regarding jee-18 help and tips.

Note by Rishu Jaar
3 years, 2 months ago

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Find the potential at a distance $\dfrac{R}{2}$ from the center of the earth, of Mass M, And have $V_{o}$ as the potential on the surface.

1) $\dfrac{3V_{o}}{8}$ 2) $V_{o} - \dfrac{11GM}{8R}$

3) $V_{o} - \dfrac{3GM}{8R}$ 4) $\dfrac{11V_{o}}{8}$

- 3 years, 2 months ago

Is (4) the ans.?

- 3 years, 2 months ago

Hmm.. i also got 4 as answer But the answer given is 3. I think both 3 and 4 are same.. isnt it?

- 3 years, 2 months ago

Nope, I don't think 3 . 4 is the final ans., moreover its formula based.simple!

- 3 years, 2 months ago

But see, 3 also gives the same thing na? $\dfrac{-GM}{R}+\dfrac{-3GM}{8R}$. So Its Also the same.

- 3 years, 2 months ago

Oh right.! Then multi-correct!

- 3 years, 2 months ago

Yeah! :P

- 3 years, 2 months ago

U did that inequality problem?

- 3 years, 2 months ago

I mean u nailed it bro!

- 3 years, 2 months ago

Why?

- 3 years, 2 months ago

It was an RMO problem. :)

- 3 years, 2 months ago

Oh i see.. Today RMO 2k17 scores are out :( . I got bad. 36

- 3 years, 2 months ago

Its nice. Believe me my friend got just 28 and he was the best.

- 3 years, 2 months ago

Is your JEE 11th course completed?

- 3 years, 2 months ago

- 3 years, 2 months ago

Yeah a school frnd this year.

- 3 years, 2 months ago

You are FIITJEE'ian?

- 3 years, 2 months ago

Nopes, no gud coaching here in my city, Mathura. I am Jksian however.

- 3 years, 2 months ago

Oh.. still your level is quite high... :) Keep it up

- 3 years, 2 months ago

A bit yeah, thnx :) ok gn , just hope the IITians answer my queries below.

- 3 years, 2 months ago

U in FIITJEE?

- 3 years, 2 months ago

Nopes...

- 3 years, 2 months ago

Ok then. All the best!

- 3 years, 2 months ago

Yeah boss

- 3 years, 2 months ago

well... i am also a jee 2018 aspirant!!!!

- 3 years, 2 months ago

Surely , you are welcome to make this discussion go on till the exam $\ddot\smile$

- 3 years, 2 months ago

Are you from FIITJEE Bhilai or Raipur?

- 3 years, 2 months ago

bhilai

- 3 years, 2 months ago

@Prakhar Bindal , @Aniket Sanghi , @Swapnil Das , @Spandan Senapati , @Harsh Shrivastava , @Md Zuhair , please initiate this discussion , With your grace.

- 3 years, 2 months ago

sure i will be more than happy

- 3 years, 2 months ago

Glad to hear it , its an honor.

- 3 years, 2 months ago

Bro I am giving JEE Advanced 2019 :). Still I will like to stay in touch with this discussion.

- 3 years, 2 months ago

Sure.

- 3 years, 2 months ago

Can you please tell how you prepared chemistry for jee , i m really Weak at it , especially organic chem.

- 3 years, 2 months ago

Also what was your revision strategy , during these last few months ?

- 3 years, 2 months ago

Please share your revision strategy for the last few months , we would be glad to know.

- 3 years, 2 months ago

@Prakhar Bindal, @Aniket Sanghi , I know you guys must be really busy, but please do answer our questions when u get free.

- 3 years, 2 months ago

Sure , mention my name for any q meant for me :)

- 3 years, 2 months ago

What was your revision strategy during these last few months...what materials you covered ? How many subjects per day ? and how Often were You active at brilliant ? please answer @Aniket Sanghi .

- 3 years, 2 months ago

Basically focus on your backlogs and simultaneously keep solving papers to keep pace. Do the things which will.increase your confidence

- 3 years, 2 months ago

Did you solved any books or just FIITJEE modules and Prev. Yr?

- 3 years, 2 months ago

I basically solved cengage , I don't solve fiitjee modules in 12th , I didn't like them . You may check my. Quora answers , in that I guess you will get answers to most of your queries

- 3 years, 2 months ago

Hey Aniket bhaiya.. If i dont get KVPY SA... am i fit for JEE Adv?

- 3 years, 2 months ago

Why not ? KVPY SA doemt define yr future , here many of my batchmates haven't cleared that still are in top 200AIR in Advance

- 3 years, 2 months ago

Really!! You have made my day and increased my confidence. Thanks :)

- 3 years, 2 months ago

(a+1/a)^10+(b+1/b)^10+(c+1/c)^10>10^10/3^9 I am trying it from 1/2an hr pls Help me a,b,c are positive reals.

- 2 years, 9 months ago

@Ayush Kumar, what should we find in the question ??

- 2 years, 9 months ago

To prove that one i.e. £(a+1/a)^10>10^10/3^9 Using Jensen's inequality.

- 2 years, 9 months ago

The inequality is not valid :

For , if it is , it should be valid for all $a,b$ and $c$

Putting $a=b=c=1$ yields wrong result.

- 2 years, 9 months ago

No it cant be we have to use Jensen's but i dont know how to apply Jensen's? Think over it.

- 2 years, 9 months ago

@Md Zuhair , KVPY SA 2017 was a useless one.....

- 2 years, 9 months ago

That doesnt matter, You Qualified, That matters. No one going to check what cheating happened in online exam, and the retest.

- 2 years, 9 months ago

But even then, KVPY exam can't decide where u stand. Reason-for maths section, I ACTUALLY DID LEAVE many questions (I wasn't getting how to solve them. Plus, whenevr it comes to RMO,INMO type questions...my situation-:[ ) And also whoevr scores awesome in KVPY doesn't NECESSARILY mean he would top IITJEE too. Coz there is bio too, and it may be possible that he went for JSO OCSC,and his Bio is a bit(TOO MUCH) strong thanks to that. Even what @Aniket Sanghi bhaiya told is correct.

- 2 years, 9 months ago

You left many questions, still qualified? Nice :) Your others were better then.

- 2 years, 9 months ago

Anyways, in JEE 19 they won't check ur KVPy mks to decide ur rank, so still no use....

- 2 years, 9 months ago

But, Do you know? I am more into Pure Science rather than Engg. So even if i qualify , I will take Phy Hons. at IIT. So IISC will be better for that.

i dont know. Lets see. If my mind changes later

- 2 years, 9 months ago

Even that doesn't matter, cuz I didn't qualify Stage-2 @Md Zuhair....

- 2 years, 9 months ago

But that doesnt define your Merit Level, The merit level is decided in first exam.

- 2 years, 9 months ago

IT DOES bro.@Md Zuhair Btw did u see the rank list ?? Almost similar to 2019 JEE Advanced Ranklist with a few subtractions(i.e. medical students)

- 2 years, 9 months ago

Ya i saw. AIR 15 is from our school! rather our section! rather.. he sits beside me :P in my bench!

- 2 years, 9 months ago

No, I mean the top 10 ranks....mostly will be the same in JEE Mains and Advanced 2019

- 2 years, 9 months ago

cuz >50 % of top 10 are the TOP GUNS of Allen Kota... @Md Zuhair

- 2 years, 9 months ago

Well, I will give you a big THANKS for always being on my side and supporting me :D. You are a good friend!

- 2 years, 9 months ago

Thank you very much brother..i will check quora also.

- 3 years, 2 months ago

- 3 years, 2 months ago

Bro in Brilliant, ppl are not active anymore so please see we have a nice group in aops(Hope Calvin sir dosent reads this :P)

- 3 years, 2 months ago

Ok got it ! :P , still we can use this discussion sometimes!

- 3 years, 2 months ago

Class 12 FIITJEE Bhilai

Wbu?

- 3 years, 2 months ago

Bro ,Class 12, Jks Academy Mathura. Probably u wud have never heard of it :P . I will catch up with you guys soon in your IITians group :)

- 3 years, 2 months ago

Are you in 11th class? Fiitjee , I guess?

- 3 years, 2 months ago

Hi Harsh , would you mind me participating in your slack group , i could use some help really, also why are you guys not much active these days ? @Harsh Shrivastava , @Spandan Senapati , @Swapnil Das , guys please reply.

- 3 years, 2 months ago

Lack of time.Mostly in 12 jee preps eat up a lot of time. As you can see I was a lot active in class-11

- 3 years, 2 months ago

Yeah i see that, btw me 2 preparing for jee , how is your performance going on at FIITJEE AITS?

- 3 years, 2 months ago

It started yesterday only. If you're talking of aiits then it's fine. Wbu? Did you appear in today's aits(adv)

- 3 years, 2 months ago

Bro , unfortunately , in my city there is a very scarce competition , also i am enrolled to a local coaching centre and haven't enrolled in FIITJEE AITS , but in Allen.

- 3 years, 2 months ago

Anyway the jee topper was from a local Centre. That Sony doesn't matter. But yes healthy competition does help a lot.

- 3 years, 2 months ago

Very true. that's why i seek a company of healthy comp. here at Brilliant, anyways , have you completed your entire JEE course? And also what are the pattern of tests conducted there at FIITJEE.

- 3 years, 2 months ago

are you there?

- 3 years, 2 months ago

Could you help me join your slack group , it would be great.

- 3 years, 2 months ago

I wish I could, sadly I am not a part of the slack group.

- 3 years, 2 months ago

OK ..then maybe @Swapnil Das or @Harsh Shrivastava might help...when they are active.

- 3 years, 2 months ago

I don't use slack bro, you should join our aops discussion, make an account on aops and done! :D

Its lot more active than brilliant.

- 3 years, 2 months ago

Ok please tell me name of your group or how to find you , i have made my account.

- 3 years, 2 months ago

No time bro. Brilliant is no more the same vibrant community it used to be.

- 3 years, 2 months ago

You are right indeed, so aren't you guys communicating like before ? I just wanted to stay in contact and get some tips from you FIITJEEians , don't mind me otherwise. $\ddot\smile$

- 3 years, 2 months ago

You're much more talented. And I'm (almost) always available.

- 3 years, 2 months ago

Oh thnx bro, not much as it seems , you are much more , by the way not on aops even?

- 3 years, 2 months ago

I have an account and I was much more active during my B'ant days. Now I'm extinct.

- 3 years, 2 months ago

ok , then aren't you in 11th...btw how are your AIITS going?

- 3 years, 2 months ago

I'm having poor health conditions right now(migraine), for which I couldn't even give KVPY. AIITS therefore went bad yesterday. I hope I recover soon.

- 3 years, 2 months ago

oh im so sorry , take care bro and get well soon , and thanx for reply.

- 3 years, 2 months ago

Hi..yup I am not that active.as I was in 11th.But still we can use it sometimes.Where do you study?

- 3 years, 2 months ago

Jks academy , mathura and you?

- 3 years, 2 months ago

Hi! I am also a jee 2018 aspirant.

- 3 years, 2 months ago

- 3 years, 2 months ago

@Tapas Mazumdar is also into JEE 2018

- 3 years, 2 months ago

But nowadays I'm less active on Brilliant than last year.

- 3 years, 2 months ago

I guess same will happen to me next year :(

- 3 years, 2 months ago

Same for me also :(

- 2 years, 9 months ago

Hey. I have a very bad news.... Not quite for u. I mailed the KVPY authorities that what was my score and I gave them my application no. They say that... No such people with that app. no gave the exam. ... I still remember that when 0:01s we're left....my computer hanged and the time wasn't increasing. So I left the computer and went out of the lab.... 😥😥😥😥😥

- 2 years, 9 months ago

I guess my paper wasn't submitted properly

- 2 years, 9 months ago

it cud be possible...anyways what 2 do.....

- 2 years, 9 months ago

What can I do other than preparing for SX?

- 2 years, 9 months ago

- 2 years, 8 months ago

Haha.... That was an Joke reply.. wasnt it? If not.. then read all the comments XD ... HAha

- 2 years, 8 months ago

@Harsh Shrivastava, how did ur Mains go ??

- 2 years, 8 months ago

Hey Aakhyat... Do u update your set of KVPY SX?

- 2 years, 8 months ago

I know, revision times + boards !

- 3 years, 2 months ago

Sure everyone is welcome.

- 3 years, 2 months ago

Guys try this : https://brilliant.org/problems/expanding-gas/

- 3 years, 2 months ago

https://brilliant.org/problems/vectors1/ , @Md Zuhair , @Mayank Singhal , try this one its cool.

- 3 years, 2 months ago

ok wait :)

- 3 years, 2 months ago

i couldn't solve Steven sir's problem:(

- 3 years, 2 months ago

Its a nice problem.. I did it :).. Its just basic concept of Electric feild+Mechanics+Trigo :P...

- 3 years, 2 months ago

That's nice..you will do good,bro.

- 3 years, 2 months ago

Do good as in?

- 3 years, 2 months ago

JEE my friend, JEE :), you have a good grip of basics.

- 3 years, 2 months ago

Not that good :P :)

- 3 years, 2 months ago

And i did ur expanding gases wala question :) . Nice... Tomorrow its KVPY. It helped me revise the polytropic process

- 3 years, 2 months ago

Hey i am getting the answer as -3

- 3 years, 2 months ago

@Md Zuhair are you getting the same answer too?

- 3 years, 2 months ago

no... im getting the correct

- 3 years, 2 months ago

Ok , so I went wrong somewhere

- 3 years, 2 months ago

Oh wait. I am also getting $3RT_{0}$ as answer.. $\Delta U=2RT_{0}$ But $\Delta H=3RT_{0}$. Isnt it?

- 3 years, 2 months ago

@Md Zuhair I am talking about the vector question.

- 3 years, 2 months ago

Ohh.. i didnt did the vector question

- 3 years, 2 months ago

@RISHU Jaar can u please check out that question again

- 3 years, 2 months ago

What about that $\Delta H$ question?

- 3 years, 2 months ago

I didn't do that one.

- 3 years, 2 months ago

Plz try and tell

- 3 years, 2 months ago

@Mayank Singhal,@Md Zuhair , both problems are correct guys.

- 3 years, 2 months ago

Okay. But isnt it that $\Delta H=C_{p} dT$?

- 3 years, 2 months ago

No that's enthalpy change , here simply evaluate by integrating $dQ=nCdT$ , right ?

- 3 years, 2 months ago

Oh yaaa :P .. See i am weak at basics :P... ThermoD. :P

- 3 years, 2 months ago

Oh i was always confused at Thermo, its a topic of confusion!:)still good.

- 3 years, 2 months ago

agreed bro, my mistake , it is -3 indeed , sorry , it was a very old problem and i didn't solved it at time of posting.

- 3 years, 2 months ago

- 3 years, 2 months ago

whose?

- 3 years, 2 months ago

https://brilliant.org/problems/vectors1/?ref_id=1425005

- 3 years, 2 months ago

how can i recorrect the answer, i have requested Calvin sir.

- 3 years, 2 months ago

Yeah.... You can say that if the scalar product is $A$,Find the value of

$A-145$. You get it

- 3 years, 2 months ago

$\large \color{#3D99F6}{\text{BRILLIANT BUDDY!}}$

- 3 years, 2 months ago

Thanks

- 3 years, 2 months ago

:)

- 3 years, 2 months ago

I have corrected it guys, thanks , now i know why the problem wasn't getting shared or liked, or even solved! :)

- 3 years, 2 months ago

i m not getting

- 3 years, 2 months ago

How to solve it -find all polynomials p(x) such that- P(x^2)={p(x)}^2.

- 3 years, 1 month ago

Hmm nice question. P(x^2)=(p(x))^2. I have seen it somewhere. Okay let me do it

- 3 years, 1 month ago

try to solve it.

- 3 years, 1 month ago

Let $p(x)=a_{0}x^0+a_{1}x^1+...+a_{n}x^n$

$(p(x))^2=(a_{0}x^0+a_{1}x^1+...+a_{n}x^n)(a_{0}x^0+a_{1}x^1+...+a_{n}x^n)$ ...$(1)$

$p(x^2)=a_{0}x^0+a_{1}x^2+...+a_{n}x^{2n}$ ...$(2)$

According to question:

$(1)=(2)$

Let's start by finding the constant term :

From $(1)$ and $(2)$ we get :

$a_{0}=(a_{0})^2 \implies a_{0}=1,0$

$\bf{Case 1}$ : When $a_{0}=1$

Continuing in the same manner and finding the coefficient of $x$ we get :

$a_{1}=0$

Setting $a_{1}=0$ in equations $1$ and $2$ and finding coefficient of $x^2$ we get:

$a_{2}=0$ .

Continuing in the same manner , we get:

$a_{1},a_{2},...,a_{n}=0$

Hence , $p(x)=1$ is a solution.

$\bf{Case 2}$: When $a_{0}=0$

Finding the coefficient of $x^2$ from equations $1$ and $2$ we get :

$a_{1}=0,1$

If $a_{1}=1$ :

$(x+a_{2}x^2+...+a_{n}x^n)(x+a_{2}x^2+...+a_{n}x^n)=(x^2+a_{2}x^4+...+a_{n}x^{2n})$

Now, divide the above equation by $x^2$ and we get :

$(1+a_{2}x+...+a_{n}x^{n-1})(1+a_{2}x+...+a_{n}x^{n-1})=x^0+...+a_{n}x^{2n-2}$

Above equation is similar to case $(1)$ with $a_{1}$ doing the work of $a_{0}$ and the degree is one less i.e,.$(n-1)$ in this case . Hence , $a_{1}$is not equal to $0$ , as we want a different solution from case $1$.

By the same reasoning , all of $a_{1},a_{2},...,a_{n-1}=0$

Finally we are left with:

$(a_{n})^2 x^{2n}=a_{n}x^{2n}$

Hence , $a_{n}=0,1$

So, the required solutions are: $p(x)=0,1,x^n$

- 3 years, 1 month ago

Is it from some Putnam exam? As far as I remember I think a similar question has been asked in some Putnam exam so where between 1970 and 1975. I think the difference was that the question in Putnam was $P(x^2+1)=P(x^2)+1$

- 1 year, 10 months ago

How was JEE Mains for you guys?

- 2 years, 9 months ago

http://cisthetaglobal.com/is-jee-2018-physics-paper-copied-from-model-paper-of-a-famous-coaching/ WHY ARE PEOPLE CREATING RUCKUS FOR THIS ?? I CANT UNDERSTAND

- 2 years, 9 months ago

That musnt be the case. I am sure. Then there will be a retest!

- 2 years, 9 months ago

A report on the same thing came in the newspaper yesterday(in my city)...and most of the institute heads are telling it isn't somthing abnormal, as Narayana itself might have copied those questions from some source and it might be a coincidence....

- 2 years, 9 months ago

Oh i see. But my brother, Can you help me ? Can you make a set in brilliant for KVPY SX questions containing PCM of KVPY level. I will also make one. It will help both of us and our juniors. Ready? You can start posting qs. I will Add them in my set!

- 2 years, 9 months ago

Hey, I just saw your New set, KVPY SX 2018. I am excited to get questions there. I have also a set. We have to work hard together to qualify KVPY SX next year. Isnt it?

- 2 years, 9 months ago

I had a small doubt bro. suppose i already have posted a question before which I want to put in my set, how to do it ?

- 2 years, 9 months ago

Its quite easy! See... What you will do is, go to the question, Click on the 3 dots written by "More" at the rightmost bottom and then click on Save. Then select the set.

- 2 years, 9 months ago

Thanks bro !!

- 2 years, 9 months ago

Sorry @Prakhar Bindal bhaiya, for posting that website link. And I m in 12th right now..

- 2 years, 9 months ago

Well guys means my elder brothers how were ur iit jee mains online or offline... i solved10 question of maths from jee mains offline...(maths was really easy)
How did u gave them?

- 2 years, 9 months ago

@Akshat Sharda , @Tapas Mazumdar , @Ayush Mishra , @Spandan Senapati . How much are you scoring in JEE ?

- 2 years, 9 months ago

@Mayank Singhal , not getting expected marks as my physics paper had gone extremely bad, chemistry was moderate, but maths was quite easy but I got only half hour for it

- 2 years, 9 months ago

Same here . Expecting 213 according to official key . What about you?

- 2 years, 9 months ago

- 2 years, 9 months ago

Did you give offline ?

- 2 years, 9 months ago

Yeah

- 2 years, 9 months ago

@Sahil Silare @Mayank Jha @Sarthak Gupta .... What about you guys?

- 2 years, 9 months ago

Got only 223 marks. Got less than expected in physics,Maths was moderate and chemistry was quite easy.

- 2 years, 9 months ago

You are chemistry topper. It will seem to that Chem is easy

- 2 years, 9 months ago

Can u plz tell me how double variable f(x)...having both x,y to be differentiated.... Like fx=9x+4y....... So as to get its min value.

- 2 years, 9 months ago

I guess for these kinds we dont differentiate. Still I am not sure.

- 2 years, 9 months ago

How much u got in maths?Question in maths was not at all tough.i was also able to solve 10 to 15 questions in it from1st part(iit jee mains offline) Dont think that i'm preparing for iit jee .im in 9th only.haha.. Hope u might be satisfied with ur marks.

- 2 years, 9 months ago

Hi bro ! How much are you scoring in advanced ?

- 2 years, 7 months ago

@Sarthak Gupta,@Mayank Singhal,@Spandan Senapati,@Harsh Shrivastava, what are ur ranks in JEE-Advanced ??

- 2 years, 7 months ago

My AIR is 1682 , marks - 197 .

- 2 years, 7 months ago

Nice Rank. You will get IIT! Congrats!

- 2 years, 7 months ago

Thanks . It is all due to this excellent brilliant community :)

- 2 years, 7 months ago

I hope you wont forget us!! :D... THe brilliant family. I hope my problems contributed to help you crack JEE?

- 2 years, 7 months ago

I can never forget it . Surely, your problems are quite good . These were one of the first problems that i solved when i first came on brilliant.

- 2 years, 7 months ago

Thanks Bhaiya. Can i have any personal contact of you? Like Whatsapp Number?

- 2 years, 7 months ago

Congratulations bro..

- 2 years, 7 months ago

Bhai tera whatsapp hai?

- 2 years, 7 months ago

@Md Zuhair as i told you 273. Well initiate the discussion...

- 2 years, 8 months ago

Yeah. How about rank? I guess within 800 ...

- 2 years, 8 months ago

722

- 2 years, 8 months ago

How are u guys?Back after a long time.

- 2 years, 7 months ago

Hey Congrats for a great rank!! I guess you will be joining IITK CSE ... :D.. Best wishes for your future. Please don't forget us :D

- 2 years, 7 months ago

@Sarthak Gupta , @Akshat Sharda , @Tapas Mazumdar, @Ayush Mishra , @Mayank Jha . How was your exam ? How many marks are you expecting ? :)

- 2 years, 7 months ago