BDMO higher secondary P6

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Asif Hossain
Posts:194
Joined:Sat Jan 02, 2021 9:28 pm
Re: BDMO higher secondary P6

Unread post by Asif Hossain » Sat Mar 27, 2021 10:01 pm

WHY BDMO GIVES SUCH HAZYYYYYYYYYYYYYYY PROOOOOOOOOOBLEEEEEEEEEEEMMMMMMMMMMMMM
Hmm..Hammer...Treat everything as nail

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Mehrab4226
Posts:230
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Location:Dhaka, Bangladesh

Re: BDMO higher secondary P6

Unread post by Mehrab4226 » Sat Mar 27, 2021 10:03 pm

Asif Hossain wrote:
Sat Mar 27, 2021 10:01 pm
WHY BDMO GIVES SUCH HAZYYYYYYYYYYYYYYY PROOOOOOOOOOBLEEEEEEEEEEEMMMMMMMMMMMMM
I know right. This is typically seen in BDMO selection and Divisional round.
For example
viewtopic.php?f=21&t=6161&p=22252&hilit ... ion#p22252
The Mathematician does not study math because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful.
-Henri Poincaré

Asif Hossain
Posts:194
Joined:Sat Jan 02, 2021 9:28 pm

Re: BDMO higher secondary P6

Unread post by Asif Hossain » Sun Mar 28, 2021 12:27 pm

Mehrab4226 wrote:
Sat Mar 27, 2021 9:45 pm
Asif Hossain wrote:
Sat Mar 27, 2021 9:36 pm
Mehrab4226 wrote:
Sat Mar 27, 2021 9:32 pm

Yes. The question said if $x$ is in $X$, then $3x$ is also in $X$. That is enough to let us know that $x$ can be any number in $X$
Didn't it said if "$x \in X$ and $3x \in S$" then $3x \in X$ :oops: :oops:
Yes, it said if $x$ is in $X$ and $3x$ in $S$. Then $3x$ must be in $X$. It implies that we cannot find any $x$ inside $X$ whose $3x$ if in $S$ not in $X$.
but it didn't said for every $x \in X$ for example if $7$ is inside $X$ but $3 \times 7=21$ isn't in $S$ but won't it be counted in $X$??
Hmm..Hammer...Treat everything as nail

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Mehrab4226
Posts:230
Joined:Sat Jan 11, 2020 1:38 pm
Location:Dhaka, Bangladesh

Re: BDMO higher secondary P6

Unread post by Mehrab4226 » Sun Mar 28, 2021 1:05 pm

Asif Hossain wrote:
Sun Mar 28, 2021 12:27 pm
Mehrab4226 wrote:
Sat Mar 27, 2021 9:45 pm
Asif Hossain wrote:
Sat Mar 27, 2021 9:36 pm


Didn't it said if "$x \in X$ and $3x \in S$" then $3x \in X$ :oops: :oops:
Yes, it said if $x$ is in $X$ and $3x$ in $S$. Then $3x$ must be in $X$. It implies that we cannot find any $x$ inside $X$ whose $3x$ if in $S$ not in $X$.
but it didn't said for every $x \in X$ for example if $7$ is inside $X$ but $3 \times 7=21$ isn't in $S$ but won't it be counted in $X$??
The question should have specified things a little more.
The Mathematician does not study math because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful.
-Henri Poincaré

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