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@Priyanshu Mishra
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nice solution. much differernt than mine. I think INMO problem setters like incenters.@Priyanshu Mishra why dont u join in the discussion in our team. U dont participate at all.

I guess you can see the last stanza of the first page of my solution. Your profile tells that your age is 14. So, I think that you are an IMO aspirant. Would you like to join us on Slack?

@Vishwash Kumar Γξω
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I saw the last stanza of the first page of your solution, but I'm not getting the value of 'a' as you got after simplifying... Can you please elaborate that simplification?

@Ojasee Duble
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That's nice if you want to join. You can join us on slack by the end of this month as the owners are into their board exams and I am also out preparing for the exams.

@Ayush Rai@Rohit Camfar - alternative method using lengths rather than angles- it uses the fact that the height from the right angle to the hypotenuse is always $\frac{ab}{c}$, and the radius of an incircle is always $\frac{ab}{a+b+c}$, where $a$, $b$ and $c$ are the lengths of a right-angled triangle and $c$ is the hypotenuse. Do this multiple times to prove that PQX forms an isosceles right angled triangle. You can also say that tangents that meet are the same length. Sorry I didn't write up all of the working, I'm in the middle of lunch:) Not going to lie, the geometry problems in this Indian MO are miles harder than those in the BMO, you guys are doing really well!

Well India is the best! And all are rest (I hope you too agree @Sharky Kesa). Well Nice solution. It is from INMO your BMO should be compared with RMO. Well try the others too @Dan Ley.

Of course haha I wish I lived in Asia. Is RMO easier or harder? I'll have a look at the 1st one some time, it looks fun, but no promises:) Yes it's 13:15 here! Showed my friends these questions, they're good!

@Vishwash Kumar Γξω
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Haha, both Liverpool and Glasgow are very far from where I live! But I understand what you mean;) So is the RMO the first round then? We have the SMC (Senior Maths Challenge) before the BMO1 (British Mathematical Olympiad)- the top 1000 do BMO1 and the top 100 then do BMO 2;)

@Ayush G Rai
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I study A-levels in Maths, Furthermaths, Physics and Chemistry:) Applied to University to do Engineering;) Are you still doing many different subjects?

Everyone lets rock. Post your solutions. Well I would like to notify some people to begin @Sharky Kesa , @Neel Khare , @Ayush Rai , @ Hrithik Nambiar , @Dan Ley , @abhishek alva Guys I don't remember anybody else's name.

I got 49- maybe I lost few marks in the 4th question where the silliest mistake of my life helped to get 4 solutions instead of 3 - of course i wouldn't have qualified even if i had got it corect.(and I had a different solution than the official ones)

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This discussion board is a place to discuss our Daily Challenges and the math and science related to those challenges. Explanations are more than just a solution — they should explain the steps and thinking strategies that you used to obtain the solution. Comments should further the discussion of math and science.

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## Comments

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TopNewestProblem 5:

Part 1

Part 2

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Nice Bro!! Both ur Solution and Bedsheet!

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hahaha.lol.Thanks

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SOLUTION TO 1

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@Rohit Camfar, same as mine.

But i calculated inradius for DEH where H is intersection of D'E with AD, instead of D'EG as both are congruent or exactly copy of each other.

That was much simpler.

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I think there would not have been much difference in solution then.

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@Priyanshu Mishra why dont u join in the discussion in our team. U dont participate at all.

nice solution. much differernt than mine. I think INMO problem setters like incenters.Log in to reply

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How did you obtain the value of 'a'?

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I guess you can see the last stanza of the first page of my solution. Your profile tells that your age is 14. So, I think that you are an IMO aspirant. Would you like to join us on Slack?

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And yeah, I would like to join you all :)

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That's nice if you want to join. You can join us on slack by the end of this month as the owners are into their board exams and I am also out preparing for the exams.

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@Ayush Rai your email. And you can first join the Brilliant's official team-- Click here

Ok, giveLog in to reply

@Ayush Rai @Rohit Camfar - alternative method using lengths rather than angles- it uses the fact that the height from the right angle to the hypotenuse is always $\frac{ab}{c}$, and the radius of an incircle is always $\frac{ab}{a+b+c}$, where $a$, $b$ and $c$ are the lengths of a right-angled triangle and $c$ is the hypotenuse. Do this multiple times to prove that PQX forms an isosceles right angled triangle. You can also say that tangents that meet are the same length. Sorry I didn't write up all of the working, I'm in the middle of lunch:) Not going to lie, the geometry problems in this Indian MO are miles harder than those in the BMO, you guys are doing really well!

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Well India is the best! And all are rest (I hope you too agree @Sharky Kesa). Well Nice solution. It is from INMO your BMO should be compared with RMO. Well try the others too @Dan Ley.

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An another thing : You wrote "Sorry I didn't write up all of the working, I'm in the middle of lunch:)" Really, are you in the middle of shool lunch?

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Of course haha I wish I lived in Asia. Is RMO easier or harder? I'll have a look at the 1st one some time, it looks fun, but no promises:) Yes it's 13:15 here! Showed my friends these questions, they're good!

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nice one @Dan Ley

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this diagram looks like ur passel of techniques problem @Rohit Camfar

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hahahah Yup I remember I too thought the same. Two circles. That too was a nice one. See this if you don't know what is Passel of TechniquesFor those who haven't seen passel of techniques

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@Ayush Rai Question: are you two at the same school?

Passel of techniques was fun;) ThanksLog in to reply

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@achal jain u can also join by giving ur email address

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@Dan Ley Are you interested?

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Problem 1:

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Everyone lets rock. Post your solutions. Well I would like to notify some people to begin @Sharky Kesa , @Neel Khare , @Ayush Rai , @ Hrithik Nambiar , @Dan Ley , @abhishek alva Guys I don't remember anybody else's name.

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and also @Priyanshu Mishra , @Md Zuhair

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@Ayush Rai, How many you solved at INMO?

I did 1, 2,4,6 only. I am uncertain about my selection.

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Problem 5 part 2. Well first part of AYUSH is the best possible. Here is a short for 2nd one.

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Problem NO 4

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We hve got our scorecards,lets share our marks

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Tell yours Ayush.. and which region are you from?

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i didnt write INMO

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I got 49- maybe I lost few marks in the 4th question where the silliest mistake of my life helped to get 4 solutions instead of 3 - of course i wouldn't have qualified even if i had got it corect.(and I had a different solution than the official ones)

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from Odisha

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