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Mathematics Optional Group UPSC 2021

People with mathematics optional who are aiming for CSE 2021, please join this discussion forum so we can have relevant discussions on issues specific to our optional subject. I have been trying to look for people with math optional online, but it is quite difficult as it is a sparse population. Most people have Sociology, Pub Ad., History, Geography as optional subjects. Libraries have the same problem. There is no currently active group on forum either. I tried civilsdaily habitat platform but the math group is inactive there. 


We can discuss strategies to finish syllabus, topics to choose (rarely does someone study all the 13 topics), discuss best source materials and books, ask specific math problems, discuss previous year papers, etc.

MikeWozniak,shivshankar_iasand14 otherslike this
46k views

89 comments


Just want to confirm if this approach is correct? The IMS solution for the PYQ contains partitioning of matrices. I don't see why we need that here. Thanks!

This seems like a really cool and intuitive approach.
I did it by the brute force method. Though the calculations got a little bit tedious but got the result in 5 steps (of which two were quite tedious and confusing where we find the determinant of the matrix C :P).


Archand,
2.7k views
» show previous quotes

This seems like a really cool and intuitive approach.
I did it by the brute force method. Though the calculations got a little bit tedious but got the result in 5 steps (of which two were quite tedious and confusing where we find the determinant of the matrix C :P).


Hey, thanks! I took some inspiration from the IMS solution, was too scared to go the brute force route! :P


Haha, I'll now do it by your method just for the fun of it. I can totally see myself spending 30 minutes only to find a teensy calculation mistake! 

chamomile,
2k views
» show previous quotes

This seems like a really cool and intuitive approach.
I did it by the brute force method. Though the calculations got a little bit tedious but got the result in 5 steps (of which two were quite tedious and confusing where we find the determinant of the matrix C :P).


Hey, thanks! I took some inspiration from the IMS solution, was too scared to go the brute force route! :P


Haha, I'll now do it by your method just for the fun of it. I can totally see myself spending 30 minutes only to find a teensy calculation mistake! 

It is almost cathartic when all the terms of the determinant (involving 12 variables in total and 4 variables per term)

cancel each other.

Feels great even when you know that you balanced and changed the subscripts of some terms just to get you to the right answer :P :P

Archand,arjunas
4.4k views
» show previous quotes

This seems like a really cool and intuitive approach.
I did it by the brute force method. Though the calculations got a little bit tedious but got the result in 5 steps (of which two were quite tedious and confusing where we find the determinant of the matrix C :P).


Hey, thanks! I took some inspiration from the IMS solution, was too scared to go the brute force route! :P


Haha, I'll now do it by your method just for the fun of it. I can totally see myself spending 30 minutes only to find a teensy calculation mistake! 

It is almost cathartic when all the terms of the determinant (involving 12 variables in total and 4 variables per term)

cancel each other.

Feels great even when you know that you balanced and changed the subscripts of some terms just to get you to the right answer :P :P

I can relate to the catharsis bit on so many levels. Chapters like Mechanics, PDE give a lot of scope to do these long calculations :P 


Hahaha. We've all been there. I'm sure you won't need it in the real exam though, all the best :)

chamomile,
2k views


Just want to confirm if this approach is correct? The IMS solution for the PYQ contains partitioning of matrices. I don't see why we need that here. Thanks!

Was going through this question a few days back and upon a few failed attempts stumbled upon this solution on the internet. It’s as simple and crisp as it gets.

chamomile,BurtMacklin_FBIand2 otherslike this
4.8k views


Just want to confirm if this approach is correct? The IMS solution for the PYQ contains partitioning of matrices. I don't see why we need that here. Thanks!

Was going through this question a few days back and upon a few failed attempts stumbled upon this solution on the internet. It’s as simple and crisp as it gets.

This is a great approach as well. More intuitive than the one I used. Thanks for this :)

1.9k views

@Archand @Celeborn Do you have the 2021 solutions? Please share if you do

Celeborn,
1.7k views

@Archand @Celeborn Do you have the 2021 solutions? Please share if you do

https://drive.google.com/drive/u/0/folders/1ZDgBKYD9ztSaRowzVD2fu_Xgtq-lD89B


Hope this helps :)


MikeWozniak,Celeborn
3.1k views
@Archand Thanks


Archand,
1.6k views
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