Question

An invitation to the brilliant community :https://brilliant.org/community-problem/wake-up-neo/?group=U7yfATIrydn6 please help solve this problem from this community and (hopefully) join. (It's your choice)

Answer 1

i think its not legal to post brilliant questions here,to get solutions!!!
but the invite itself is good

Answer 2

i just inviting them I solve it myself I just wanna see others solutions if that cheating sorry but the only way to invite is to give them a good problem and get them interesting in the exciting world of math.

Answer 3

thats great...i like the community,thanks 4 the invite

Answer 4

invite people yourself spread the world to mathematics that anyone can do just practice.

Answer 5

alright guys this is a super hard problem if you can solve this you are a genius and I commend you and welcome to join our Free open community if you can't solve this and still have a love of math the you are still welcome to join everyone is.

Answer 6

@Loser66 I got the same thing I just can't figure out how to prove it.

Answer 7

Yes I do

Answer 8

please my brain from thinking too long

Answer 9

it burns

Answer 10

No way your genius do you like math I've been trying to find a proof for 30 mins I have attention so concentrating for that long is super hard. Wanna join in ?

Answer 11

your solution is right why did you erase it @Loser66 it was amazing

Answer 12

@Jonask what type of way did you get your solution ?

Answer 13

this is same approach as @Loser66
we count \[2\le i, j\le 40\]
\[S=\large \sum_{i,j} ij=\sum_1^{40} i\sum_1^{40} j=(\sum _1^{40 }i)^2=(1+2+...40)^2\\=\frac{40(41)}{2}=820^2\]
\[\sqrt{S}=820\]

Answer 14

but it is waaaaaaaaaaaaaaay mathematics than mine, hehehe... admire.!!

Answer 15

oppps i missed a square\[ (\frac{40(41)}{2})^2\]
thanks to the Winner @Loser66,you shud changer ur name to Winner96...i admired your approach a lot

Answer 16

I use a different way the I actually made the matrix deleted forgot the answer remembered it but forgot how to do it I swear I'm so stupid sometimes and Loser66 thanks so much for being so smart your really should change your name to what @Jonask suggested and join the community to you should see what solution they came up with there people you just waiting to discuss

Answer 17

@Loser66

Answer 18

please join guys it will be fun there are more brilliant problems and practice.

Answer 19

what do you say ?

Answer 20

hehehe. I am a lazy student. I don't deserve any thing but if you say I can observe only or contribute whenever I like , I would like to join

Answer 21

of course just go to brilliant.org and join there always room for more

Answer 22

ok, let me figure out what it is, then sign up. Thanks for suggestion.

Answer 23

yes i got member and welcome to the world of math Winner