BDMO higher secondary P6
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Please don't post problems (by starting a topic) in the "X: Solved" forums. Those forums are only for showcasing the problems for the convenience of the users. You can always post the problems in the main Divisional Math Olympiad forum. Later we shall move that topic with proper formatting, and post in the resource section.
Please don't post problems (by starting a topic) in the "X: Solved" forums. Those forums are only for showcasing the problems for the convenience of the users. You can always post the problems in the main Divisional Math Olympiad forum. Later we shall move that topic with proper formatting, and post in the resource section.
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WHY BDMO GIVES SUCH HAZYYYYYYYYYYYYYYY PROOOOOOOOOOBLEEEEEEEEEEEMMMMMMMMMMMMM
Hmm..Hammer...Treat everything as nail
- Mehrab4226
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Re: BDMO higher secondary P6
I know right. This is typically seen in BDMO selection and Divisional round.Asif Hossain wrote: ↑Sat Mar 27, 2021 10:01 pmWHY BDMO GIVES SUCH HAZYYYYYYYYYYYYYYY PROOOOOOOOOOBLEEEEEEEEEEEMMMMMMMMMMMMM
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
-Henri Poincaré
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Re: BDMO higher secondary P6
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 $X$??Mehrab4226 wrote: ↑Sat Mar 27, 2021 9:45 pmYes, 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 $X$.Asif Hossain wrote: ↑Sat Mar 27, 2021 9:36 pmDidn't it said if "$x \in X$ and $3x \in S$" then $3x \in X$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 $X$
Hmm..Hammer...Treat everything as nail
- Mehrab4226
- Posts:230
- Joined:Sat Jan 11, 2020 1:38 pm
- Location:Dhaka, Bangladesh
Re: BDMO higher secondary P6
The question should have specified things a little more.Asif Hossain wrote: ↑Sun Mar 28, 2021 12:27 pmbut 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 $X$??Mehrab4226 wrote: ↑Sat Mar 27, 2021 9:45 pmYes, 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 $X$.Asif Hossain wrote: ↑Sat Mar 27, 2021 9:36 pm
Didn't it said if "$x \in X$ and $3x \in S$" then $3x \in X$
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
-Henri Poincaré