nnn
D6 chinh ld li do d6n d6n k6t qu6 sai: 1 : 0 !
NhQn xet Nhi6u b4n dd tham gia bdi ndy nhrmg chi c6cdc b4n sau phdt hi€n dung sai lim: cdc b4n sau phdt hi€n dung sai lim:
Hir NQi: Dinh Chdu Anh, 12A1, THpT H6 Xu6n
Huong, s5 t, Nguy6n Qulf Dric, Q. Thanh Xudn. Hung YGn: Tri€u Ninh Ngdn, 12A9, Nguydn Thi phuong
Oanh, l1Al, THPT Ducrng Quing Hdm, Vdn Giang.
Vinh Long: LA Minh Qudn, 11T1, THPT chuy6n
Nguy6n Binh IGi6m.
sO H6NG TONc euAr
c0l nAv so:
Ddy s6 li m6t chuyCn dd quan trong trong b6idu&ng hgc sinh gi6i. Trong chuyCn tIC day s6 c6 du&ng hgc sinh gi6i. Trong chuyCn tIC day s6 c6 bdi torin quen thu6c sau:
Biri torin. Cho diiy tti \u,,\ thda mdn;
IEI !J I !J | 1t - - t: i^t.I tr. -2-rt| Itt ==-!- n =, \ t t+r..6 2\tr,,
Tim s6 hang tOng qnat u,,.
Ldi gidi. Ta c6: ^lT ^lT '2tan - ranL:an2.L= 12 : t: 6 '-- 12 r- | - tan2 /t VJ l2
<+ tan2 ! 12 + zJl tan i 12 -t :0 <> tan L t2 = z - J1.
tanE +tanz , \
-. 6 12 (E n\
r/,=-=tanl _*_l:
t-tanfthn! (o l2)'612 612
Bing quy nap ta chimg minh duoc
(z -\
u.:tanl " \6 -+tn-l.L ',12)l. vr> t
Cdc bgn cd nhQn xit gi vi mi tudn vd ldi girtitr0n? tr0n?
PHAM QUANG HTNG (GV THPT chuyAn Thdi Binh)
ta.ruo-rrrz T?8I#8E 39 & "wmru Mry-,#tr %;ffi t; VJE 36 =an(1*z.L).(6 12) KIHI\rI 7T + tan t2 1T Z\ -+ I 6 t2)
lqr thi Imn [0( un Tll0l T[t
I$uthendia und hulh lrlngudne
xuAT n(r,t rtJoel
sd47s (1.2017)Iia s0an : Ii'ng 12, Toa nhi Diam0nd tlowel, Iia s0an : Ii'ng 12, Toa nhi Diam0nd tlowel,
S0'1, Hoanq 0Ao lhtiY, Hi iloi
DT Bion la[: 04.351 21 607, 0T - tax Phet hanh, IIi su : 04.351 21 606
Email: l0anh0ctu0illeuielnam@gmail.c0m
atx cci vix ruron ruqc
71
GS, T SKH. NGTIYEN CANH TOAN
GS. T SKH. TRAN VAN NHLINGrs. NcuvgNvaNvo.Nc rs. NcuvgNvaNvo.Nc
cs. ooaN qrrirrur
Pcs. rs. rnANvANneo
ruor n6Nc atEN rtp
IHIU rnAcn xufiu xuir nAx
Chir tich Hoi ddng Thanh vi6n NXB Gi5o duc Vi6t Nam
MACVaNTTUS-N
Tdng Gidm ddc NXB Gi6o duc Vi6t Nam cs.rs.v0vaNrnxc
Ph6 tdng Gi6m ddc ki6m Tdng bi6n tdP
NXB Gi6o duc Vi€t Nam Ts. PHANxUANTHANH
Thu ki Tda soan : ThS.ffd quaNC VfNu Tdng bian hip : TS.TRAN HUU NAM
zs. rnAN oNs csAu, zl,s. Ncuy6N eNn ofxc, rs. rnAN NRM tfD.tc, rs. NcuvfrN vrNn oOc, rs. ucuvit'i MINH HA,
il.'i.,.-C.u"ril-
"iir-"".,-"^.-ir.-iE-ar5; sAN, rrs. pH4,M vAN sirxc, rcs. rs. vu rHANH rm6r,
Cr. rrr".-*-i-,ti
"or rarlorr *o"*J"*. MrNH, zs. IHAM rHI BACH NGoc, PGs. ?s. NcuvEN oANc pnir,
pcs. rs. rA Dlly pHrxfirc, rrs. NcridN rn6 mrecu, GS. TSKH.DANG HttNG ruiNc, PGs. rs. pnaN ooAN rsoeI, rm. vU zuu truv, PGs. rs. vO DtJoNG THVY, cs. rsra. NcO vGr rnuNc.
TRONG SO NNY
@ oanr, cho Trung hgc Co s&
@ HuOrrg d6n giAi Dd thi chon hoc sinh gi6i @ ciai bei ki trtt'dc
For Lower Secondary School
Nguydn Thi Nhung - Giai phrrong trinh
nghiQm nguy6n bing phriong ph6p sit dung
tinh chdt chia hdt.
m6n To6n 16p 9 tinh Vlnh Phric, ndmhoc 2015 - 2016. hoc 2015 - 2016.
@ oitin dAn d4y hgc To6n
@ OU thi chon hoc sinh gi6i 16p 9 tinh Hung Yon,
nim hoc 201,5 -2016.
@ ffrrf st?c trtt'dc ki thi - Dd s6'5.
@ ,u, 6n vi hrrdng dAn g'iAi dd s6'+. @ fftoong ph6p giAi to6n
@ tiArrgAnh qua cic bAi toAn - Bdi sdl6
Bhi dich sd tg - TidngAnh q:uacdcbdi to6n
@ s"i ldm & dau?
@ r,i"r, sr? To6n hgc
Ii Qudc Hd,n - Pappus, ng6i sao la trong bAu
trdi to6n hoc Hy I+p cd dai.
@
"Un
dgc tim tdi
Nguydn Phi Mang - Tr1 gi6c di6:u hda drr6i c6ch nhin cria ph6p nghich d6o.
Gi.d.idd,p:7=01
Nguy\n Quang HnnSqu6t ctra ddy sd ! qu6t ctra ddy sd !
@ ti', ttt"
LA Mai - Gdn giAi duoc gi6 thuydt ydu cria Goldbach.
@ oO ra ki'niy
Problems in This Issue
Tu47 5, ..., Tl2l47 5, LLl47 5, Lzl 47 5.
Solutions to Prettious Problems
Nguydn Ldi - Pl::lrang ph6p lAp bdt d&ng
thrlc phg dd chirng minh m6t dang bdt
d&ng thfc.
Trd.n Xud.n Dd.ng - MQt sd Phrrong Ph6P tim him li6n tuc trong phuong trinh him.