Search found 312 matches
- Wed Mar 12, 2014 2:55 pm
- Forum: Algebra
- Topic: Calculate the sum
- Replies: 1
- Views: 2240
Calculate the sum
$6+66+666+6666...+\underbrace{666...6} n6's (n\geq 1)$
- Wed Mar 12, 2014 2:36 pm
- Forum: Number Theory
- Topic: Find the last three digits
- Replies: 3
- Views: 3153
Find the last three digits
What are the last three digits of the number $7^{9999}$
- Wed Mar 12, 2014 2:32 pm
- Forum: Geometry
- Topic: Prove the length
- Replies: 0
- Views: 1595
Prove the length
Let $ABC$ be a triangle with sides of lengths $a,b,and c$.Let the bisector of the angle $C$ cuts $AB$ in $D$.Prove that the length of $CD$ is: $\frac{ 2ab cos \frac{C}{2}}{a+b}$
- Mon Mar 10, 2014 7:44 pm
- Forum: Number Theory
- Topic: Asking for essential books
- Replies: 1
- Views: 2261
Asking for essential books
What books are essential for junior category on Geometry,Number Theory,Combinatorics etc topic
Is there any website from where can I download them
Is there any website from where can I download them
- Sun Mar 09, 2014 10:16 pm
- Forum: Number Theory
- Topic: quadripple equation
- Replies: 8
- Views: 5277
Re: quadripple equation
Moon via,why have you taken $mod 4$???
- Thu Mar 06, 2014 10:13 pm
- Forum: Junior Level
- Topic: prince number
- Replies: 5
- Views: 4604
Re: prince number
What is the sign $\left \lfloor \right \rfloor$ means ???
- Tue Mar 04, 2014 12:16 pm
- Forum: Geometry
- Topic: Secondary Special Camp 2011: Geometry P 3
- Replies: 3
- Views: 3685
Re: Secondary Special Camp 2011: Geometry P 3
Zzzz via,you wrote:$\frac{BD}{CD}\times \frac{CE}{AE}\times \frac{AF}{FB}=1$.So,D,E,F collinear.Why!
- Mon Mar 03, 2014 6:06 pm
- Forum: National Math Olympiad (BdMO)
- Topic: Junior 2014/9
- Replies: 2
- Views: 2407
Re: Junior 2014/9
Sorry,for the mistake.I did not see it before.
- Sat Mar 01, 2014 7:53 pm
- Forum: National Math Olympiad (BdMO)
- Topic: Junior 2014/9
- Replies: 2
- Views: 2407
Junior 2014/9
If N is an even integer,prove that 48 divides $N(N^{2}+20)$ Solution: As N is an even number,N is of the form 2m.Now the equation is : $N(N^{2}+20)$= $2m((2m)^{2}+20)$= $2m(4m^{2}+20)$ = $8m^{3}+40m$ =$8m(m^{2}+5)$.If the expression is divisible by 16 and 3,then it also divisible by 48.Now in the ex...
- Wed Feb 05, 2014 9:57 pm
- Forum: Geometry
- Topic: Asking suggesion for BdMO 2014
- Replies: 3
- Views: 3051
Re: Asking suggesion for BdMO 2014
Please!Please!Give suggestion