da eto tochno. Pust 2 premiye odna iz kotorih diagonal 4ugolnika a vtoraya pramaya kotoraya prohit cherez toshki kasaniya M ,N peresikayutsa v toshke X. togda zapishem Menelaya k pramoy kotoraya prohit cherez toshki kasaniya M,N .
A drugiye tochki K,L budut lejat na pramoy prohodashih iz X

skorey sego nado ispolzovat teoremu menelaya . ya kogdato reshil eyo do teh vremon poka ne popal na zbornuyu UZB na IMO merida

been writing it with a lot of mistakes. wow! i have done a lot of 'em in the examination and thought that i wont enter there but the things are not so bad anyway...


got a question: Do the Muirhead theorim works with the cyclic sums?

ya postupil v tot universited

spasibo za zadachi . Reshal oblastnoy uje zakonchil teper est o chom dumat.

mojete li vi preslat mne zadachi proshedshih v etom godu olimpiad na rustamtm@yahoo.com . Budu jdat.spasibo

zadachi bili legkiye 1.dokazat teoremu chevi 2.pervaya zadacha iz knigi zarubezniye matematicheskiye olimpiadi iz 2 paragrafa(2.1) 3.dokazat sin20gradusov<7/35 kajetsa 4.esli a+b=1 to dokazat chto a^4+b^4>1/8 5.dakazat chto summa kubov 3 posledovatelnih naturalnih chisel delitsa na 9. 6. vne dannoy ...

Spasibo za resheniya. Okazivaetsa ya dumal sovsem ne tak kak doljen bil. U menya bivaet tak chto ne mogu ponyat zadachi na drugix yazikah. Esli vi govorite chto zadachi legki pobrobuyu esho ras. Ya zakanchivayu perviy semester moyego uchebnogo goda,sessiya, eksamini........... Nam olimpistam ne dayu...

Dlya nachalo mogetele vi otpravit mne resheniya ili ukazaniya k zadacham 9-klass 3-etapa krome 1 i 3 zadachi pojaluysta.

Mogete le vi prislat mne resheniye 3-etapa XXX-vserossiyskoy olimpiadi a to cho to nectoriye zadachi ne poluchaetsa reshat.Na vash vopros hotel otvetit:ya reshayu zadachi is vsakih uchebnikov i novih zadach poshti ne reshayu. Vot i reshil ya zanatsa s nomimi zadachami nachinaya s rossiyskoy olimpiadi.

Izvenite ya hotel skazat cho doljno bit x-2=0. Iz etogo sleduet chto x=2 i a=4.ya hotel skazat cho mi perepishen uravnenie sqrt(x^2-4x+5)+sqrt(x^2-4x+13)=a v vide AB+AC=a.

Ya reshil chto eti zadachi legki potomu chto za gdeto 4.5 chasov ya smog reshit vse zadachi. Vot odno iz moih resheniy dlya zadachi dlya 10 klassa : vozmom tochki na koordinatah A(x-2;0) , B(0;1) , C(0;3).dlya kotorih a=AB+AC dlya kogogonibut a. esli x ne raven 0 to tochka D(2-x;0) toje udavletvarae...

ya poluchil zadachi.
Spasibo bolshoye za udeleniye mnimaniye mne.
Mne kazutsa oni ne trebivayut osobiye trudnosti.
Mogeteli vi prislat mne zadachi 3-tura.

U nas sistema takova: 1) shkolnaya olimpiad dlya 9,10,11 klassa 2) rayonaya olimpiad dlya 9,10,11 klassa 3) gorodskaya olimpiada dly gorojaninam dlya 9,10,11 klassa 4) Oblastnaya olimpiada dlya 9,10,11 klassa 5) respublikanskaya olimpiada dlya 9,10,11 klassa Dlya uchenikov akademicheskix litseyah i ...

a kak udalyat sobsheniya?