Hi Brilliant!

I have been in a bad form(not in a good frame of mind) recently. That's solely because of my inability to solve combinatorics problems. IIT-JEE is around the corner an I want to get to the level of IIT-JEE (around 250 points problems). I've read many books for IIT-JEE (combinatorics section especially) but still I feel there's some flaw in my understanding of concepts in combinatorics. I do not go to any coaching now as I feel self studying is more important at this time. That's why I'm asking you for help. I do not have deep interest in combinatorics as much I have in calculus. My inability to solve problems in combinatorics has lead to frustration and poor performance in other subjects. I don't want to ruin my IIT-JEE. Please help.

Please share good techniques (which can be generally used for problem solving), theories (which generally come in exams) and some sources.

Another problem is time factor. I don't have much time to read fat books, etc.

Any sort of help will be appreciated :)

## Comments

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TopNewestTry to understand these by putting a strain on your brain

1.Inclusion Exclusion Principles(very useful for problems involving functions in combinatorics)

2.Derrangements

3.Difference between division and distribution

4.Difference in permutations and combinations of identical and unidentical objects

5.Circular permutations

Yes combinatorics does require a bit of jugglery. Try to solve each and every possible question of combinatorics of previous year jee papers after learning the above concepts. We are always here.. ;) – Rohit Ner · 5 months, 1 week ago

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– Aditya Kumar · 5 months, 1 week ago

ThanksI I shall start from now itself! (:Log in to reply

I would suggest Principles and Techniques in Combinatorics by Chen Chuan-Chong, Khee-Meng Koh

It covers all the techniques required for JEE combinatorics, and has lots of solved examples. – Pranshu Gaba · 5 months, 1 week ago

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– Aditya Kumar · 5 months, 1 week ago

Thanks I got the PDF. It is really a good book. (:Log in to reply

– Pranshu Gaba · 5 months, 1 week ago

You are welcome :)Log in to reply

– Samarth Agarwal · 5 months, 1 week ago

Pls share the linkLog in to reply

– Aditya Kumar · 5 months, 1 week ago

That book is too expensive. Do you have a PDF of it?Log in to reply

– Rajdeep Dhingra · 5 months, 1 week ago

I have. I used it for RMO long back. (Again going to start using it :P)Log in to reply

– Samarth Agarwal · 5 months, 1 week ago

If u have pdf pls shareLog in to reply

here – Aditya Kumar · 5 months, 1 week ago

Download it fromLog in to reply

– Samarth Agarwal · 5 months, 1 week ago

Thanks!!Log in to reply

Okay, since you mentioned JEE only, I'll tell you the way to practice that worked for me - the Archives (past JEE papers). Try solving every combinatorics question, and if you can't, read the theory/solution and proceed. Try this out, and tell me if it works. – Ameya Daigavane · 5 months, 1 week ago

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Sir if u have time do watch mohit tyagi on youtube . He is a very good teacher and will be quite helpfull to u in your P & C – Gauri shankar Mishra · 5 months, 1 week ago

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– Aditya Kumar · 5 months, 1 week ago

Rajdeep had linked me those series of videosLog in to reply

– Gauri shankar Mishra · 5 months, 1 week ago

Have u seen any of them they are indeed very goodLog in to reply

Try Brilliant Wikis. – Samuel Jones · 5 months, 1 week ago

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– Aditya Kumar · 5 months, 1 week ago

Yes I saw them (:Log in to reply

@Sandeep Bhardwaj One your Quick Notes is needed. :) – Rajdeep Dhingra · 5 months, 1 week ago

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I sent you something on slack. Check it out. Your PnC level will boost 5 times with that. – Rajdeep Dhingra · 5 months, 1 week ago

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– Samuel Jones · 5 months, 1 week ago

Do you mind sharing it here too? Thanks!Log in to reply

– Aditya Kumar · 5 months, 1 week ago

That video is in Hindi. Do you know Hindi?Log in to reply

– Siddhartha Srivastava · 5 months, 1 week ago

I do. Link?Log in to reply

Remember these(some of them might be quite easy for you):\[\] 1)Whenever solving P and C probs,this 'mantra' works for me,First,find out the number of ways to 'combinate'(if you know what I mean),and then permute it.\[\]2)Always remember that whenever you are taking product,you are permuting.\[\]3)Try this. \[\] I hope this helps! – Adarsh Kumar · 5 months, 1 week ago

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– Aditya Kumar · 5 months, 1 week ago

Thanks!Log in to reply

This might help. :) – Mehul Arora · 5 months, 1 week ago

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– Aditya Kumar · 5 months, 1 week ago

Thanks!Log in to reply

Here

This might be too easy

Practice all of these

Hope it helps. – Mehul Arora · 5 months, 1 week ago

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– Aditya Kumar · 5 months, 1 week ago

I saw many of them.Log in to reply

– Mehul Arora · 5 months, 1 week ago

Great, then practice more. All the best! :)Log in to reply

– Aditya Kumar · 5 months, 1 week ago

Thanks!Log in to reply

– Ayush Shridhar · 5 months, 1 week ago

btw where are you now?Log in to reply

– Aditya Kumar · 5 months, 1 week ago

I'm in Bangalore. My dad is transferred. I'll come back to Mumbai on 10 May.Log in to reply

– Ayush Shridhar · 5 months, 1 week ago

So you wont give any fiitjee test now?Log in to reply

– Aditya Kumar · 5 months, 1 week ago

Apparently no. But I'll give the last one on 15 May.Log in to reply

– Ayush Shridhar · 5 months, 1 week ago

Okay! How was mains?Log in to reply

– Aditya Kumar · 5 months, 1 week ago

Bad getting only 200Log in to reply

this – Aditya Kumar · 5 months, 1 week ago

SeeLog in to reply

– Rishabh Singhal · 2 months ago

Can you please tell me some sources on the topics of special functions (polygamma, gamma,etc) and summation...it would be really helpfulLog in to reply

wiki pages. – Aditya Kumar · 2 months ago

Explore theLog in to reply

– Rishabh Singhal · 2 months ago

Thanks for the reply! But it seems that link is not working now..Log in to reply

– Ayush Shridhar · 5 months, 1 week ago

Okay!Log in to reply