# Relationship between perfect splitting and surface contact area (Circles)

Check this out first before reading this. Basic information will not be repeated in this post.

Surface area of a sphere:

$\boxed{4πr^2}$

After a perfect split:

$\frac{4πr^2}{2} + πr^2$

Which then becomes:

$2πr^2 + πr^2$

And it finally becomes:

$\boxed{3πr^2}$

This is also the same formula for the surface area of a hemisphere

Note by A Former Brilliant Member
3 months, 2 weeks ago

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## Comments

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Am I the only one who finds it funny that this note is about some relationship and we're talking about friendship, a kind of relationship. its like its destiny. LOL

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YOU can't hide forever @Yajat Shamji, just reply.

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I am.

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Good.

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Don't message from 6-7 coz I'm suuuper busy watching TV.

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Nice @Hamza Anushath

- 3 months, 2 weeks ago

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Thnx :D

- 3 months, 2 weeks ago

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No problem. Also, did you reply to my Mersenne comment in the Report Room? @Hamza Anushath

- 3 months, 2 weeks ago

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I should check it out

- 3 months, 2 weeks ago

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Hello, @Hamza Anushath? It's been $2 - 3$ weeks since you were last active. What are you doing? I am becoming frantic to talk to you! Where are you? What are you doing? I am admitting, you are my first BRILLIANT friend, okay? So, please, I beg you, come back...

- 3 months, 1 week ago

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Oh right... Most sorry @Yajat Shamji

Just that I had a break before.

I started with Brilliant again today (you might have noticed me not posting solutions anymore)

Happy to know that you were waiting, but sorry to keep you waiting

- 3 months, 1 week ago

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Ok. I thought I was going to have an emotional breakdown in bed! Thank God! You're back!

Check out what I have done today and recently:

lInternational Mathematical Olympiad (IMO) Hall of Fame

International Mathematical Olympiad 2019, Day 2, Problem 4 of 6

- 3 months, 1 week ago

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:D

I will check them all then...

- 3 months, 1 week ago

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You not going to say anything about the admitting or...

- 3 months, 1 week ago

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Quite hard for me... But I'll try!

- 3 months, 1 week ago

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You do realise the definition of BRILLIANT friend or...?

- 3 months, 1 week ago

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Yes, I do

But I feel like it is quite hard...

I dunno, I will try my best!

- 3 months, 1 week ago

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The reason why I admitted it is that when I am talking with other people, I feel nothing. But when I am talking with you, I feel a sense of peace, purpose, togetherness. I also feel happiness in talking to you.

- 3 months, 1 week ago

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(°O° )

Thnx a lot @Yajat Shamji (I mean it)

You surely did make my day!

- 3 months, 1 week ago

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@Hamza Anushath, check out this problem I just made...

- 3 months, 1 week ago

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@Yashvardhan Pattanashetti, I had a lunch break - I am doing Virtual School - I follow the timetable strictly.

So...

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@Hamza Anushath, I know I said don't reply until tomorrow, but, after much deliberation, I have decided to forgive you. You can reply now.

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Good choice.

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Thanks @Yajat Shamji

:D

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@Frisk Dreemurr - Isn't this like basic info that you're taught in 6th or 7th grade? Why did your past self make a note on this?

- 1 month, 2 weeks ago

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@Percy Jackson, LOL

- 1 month, 2 weeks ago

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@Hamza Anushath, are you a girl or boy?? (I'm not weird or an idiot, Pall Marton confused me).

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Female, to be precise

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Páll Marton told me you're a guy. LOL

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