## Search found 26 matches

- Thu Feb 14, 2013 9:41 am
- Forum: Secondary Level
- Topic: Geometry Note
- Replies:
**6** - Views:
**2902**

### Re: Geometry Note

Adib Bhai if you have time can you please translate your note in English. Students like me, coming from English medium background find geometry very difficult as our curriculam has very little geometry. And your note is indecipherable for me due to the language barrier.

- Tue Feb 12, 2013 7:14 pm
- Forum: Secondary Level
- Topic: Number Theory Proof please
- Replies:
**1** - Views:
**1397**

### Number Theory Proof please

If $e=\frac{a}{b}=\frac{c}{d}$, where $b>d$ and $a>c$ prove that $e=\frac{a-c}{b-d}$

I know it is true but have failed to prove it. Can someone pull me out of this misery please?

I know it is true but have failed to prove it. Can someone pull me out of this misery please?

- Mon Feb 11, 2013 6:43 am
- Forum: Social Lounge
- Topic: Help...
- Replies:
**3** - Views:
**2546**

### Re: Help...

1) Geometry Revisited - H.S.M. Coxeter 2) 104 Number Theory Problems - Titu Andreescu, Dorin Andrica, Zuming Feng 3) Elementary Number Theory - Jones and Jones 4) The Art and craft of Problem Solving - Paul Zeitz. P.S. 4) is an all in one book that contains all of Number Theory, Algebra, Calculus. M...

- Sun Feb 10, 2013 5:00 pm
- Forum: Divisional Math Olympiad
- Topic: Please Post the Problems of 2013
- Replies:
**7** - Views:
**3758**

### Please Post the Problems of 2013

BDMO is over. Moderators please upload the divisional round questions in the forum.

@Moon Bhai, upload the national round problems formally please.

@Moon Bhai, upload the national round problems formally please.

- Thu Feb 07, 2013 9:03 pm
- Forum: National Math Olympiad (BdMO)
- Topic: BdMO National Higher Secondary 2007/7
- Replies:
**6** - Views:
**3844**

### Re: BdMO National Higher Secondary 2007/7

How does the green line lead to the red line?nafistiham wrote: here, $x^7-1=f(x)\cdot(x-1)$

so, \[f(x)|(x^{42}-1),(x^{35}-1),(x^{28}-1),(x^{21}-1),(x^{14}-1),(x^7-1)\]

so, the remainder will be

\[7\]

- Thu Feb 07, 2013 8:59 pm
- Forum: National Math Olympiad (BdMO)
- Topic: Let us help one another preparing for BdMO national 2013
- Replies:
**12** - Views:
**6681**

### Re: Let us help one another preparing for BdMO national 2013

What does the portion in red mean???Shadmanmajid wrote:Problem no.3- For a positive integer n, ﬁnd the number of solutions of the congruence x

2 ≡ 1 (mod n).

- Thu Feb 07, 2013 7:08 pm
- Forum: National Math Olympiad (BdMO)
- Topic: BdMO 2010 higher secondary Q. 6
- Replies:
**7** - Views:
**3417**

### Re: BdMO 2010 higher secondary Q. 6

$a^2\equiv0^2,1^2,2^2,3^2,4^2\equiv0,1,-1,-1,1 (mod5)$ There are $804$ numbers of form $5n+2$ and $5n+3$ less then $2010$. There are $804$ numbers of form $5n+1$ and $5n+4$ less then $2010$. There are $401$ numbers of form $5n$ less then $2010$. So that number of pair $(a,b)$ be $2.804^2+401^2$. An...

- Wed Feb 06, 2013 9:39 pm
- Forum: Secondary Level
- Topic: Help with BDMO Problems
- Replies:
**1** - Views:
**1503**

### Re: Help with BDMO Problems

Check this link. Here you will find all the 2012 BDMO Nat. Problems with threads after each problem. You will find your desired solutions once you go to the threads. CLICK: viewtopic.php?f=13&t=1708

- Wed Feb 06, 2013 7:09 am
- Forum: Higher Secondary Level
- Topic: Secondary and Higher Secondary Marathon
- Replies:
**127** - Views:
**57315**

### Re: Secondary and Higher Secondary Marathon

Probelm $37$: $\mathbb{N}$ is the set of positive integers and $a\in\mathbb{N}$. We know that for every $n\in\mathbb{N}$, $4(a^n+1)$ is a perfect cube. Prove that $a=1$. Source: Iran NMO-2012-4. Note: In BdMO Summer Camp-2012, a similar problem was given in the Number Theory problem set. Zubaer vai...

- Tue Feb 05, 2013 9:59 pm
- Forum: National Math Olympiad (BdMO)
- Topic: BdMO National Secondary 2011/9
- Replies:
**11** - Views:
**5475**

### Re: BdMO National Secondary 2011/9

Can it be generally said that $\sqrt{a}+\sqrt{b}$ and $\sqrt{a}-\sqrt{b}$ is always irrational if both $\sqrt{a}$ and $\sqrt{b}$ are irrational? I think it is because in Secondary and higher Secondary Marathon Adib Bhai had asked for a similar proof which Sanzeed Bhai proved. Also, during the olympi...