d`elb zxeze zecyd zxeza dxfg zel`y? R lrn miwixt-i`d minepiletd mdn (1 :mipiievnd zecyd lrn miwixt-i` mi`ad minepiletd ik egiked (2 Q( 2) lrne Q lrn X 3 3 (`) Q lrn X 4 + 1 (a) Q lrn X 3 5X 2 + 2X + 1 (b) F 7 lrn X 7 X 1 (c) R(t) lrn X 3 t (d) α+1 mbe α mb ik gippe,owezne wixt-i` mepilet f F [X] `di,dcy F `di (3.iaeig oeit` F -l ik egiked.f ly miyxy ly wixt-i`d mepiletd zlrn ik egiked (4 2(1 3) i 5 2004 + 7 + 3 9.96 z` zwlgn Q lrn f(x) ik e`xd. Q-a f(x) ly yxy α `die f(x) = X 3 + 2X + 2 `di (5.1, α, α 2 ly zix`pil divpianewk 1/(1 + α) z` ebivd.q lrn wixt-i`.q( 3 2 3) = Q( 3 2, 3) ik egiked (6.α = 2 + 3 2 iynnd xtqnd ly Q lrn wixt-i`d mepiletd z` eayg (7.C-a eiyxy lk z` e`vn,df mepilet ly α yxyl.wixt-i` X 3 X + 1 Q[X] mepiletd ik egiked (8.irr(α 2, Q) z` e`vn.f 2 lrn 3 dlrnn miwixt-i`d minepiletd lk z` e`vn (9 dlrnn wixt-i` mepilet f F [X] `die ziteq zecy zagxd E/F `dz (10.E-a yxy f -l oi` ik egiked.1-n dlecbde [E : F ]-l dxfd egiked.zibef-i` irr(α, F ) zlrn ik gipp.f dcyd lrn ixabl` xa` α `di (11.F (α) = F (α 2 ) ik jk F p mi`znd ipey`xd dcyd lrn f(x) minepiletl zyxetn `nbec epz (12.mixa` 27 e`,8, 9 oa dcy epid F p [X]/ f(x) -y.f 8, F 9 ly ltkde xeaigd zegel z` ex`z (13 1
2. 1 dlrnn wixt-i` mepilet f E[X] `di.zixabl` dagxd E/F `dz (14.f(X) g(x)-y jk g F [X] cigi wixt-i`e owezn mepilet miiw ik egiked.(f p : (F p ) 2 ) = 2,ipey`x p 2 lkl ik egiked (15 ipey`x lkl ik egiked.f(x) = (X 2 2)(X 2 3)(X 2 6) Q[X] `di (16 oi` f(x)-l mle`,f p -a yxy yi p elecen f(x) ly f(x) F p [X] divwecxl,p.q-a yxy :mipiievnd zecyd lrn mi`ad minepiletd ly levitd zecy z` eayg (17 Q lrn X 3 5 (`).F 5 lrn X 3 2 (a) F 5 lrn X 6 + X 3 + 1 (b) Q lrn X 4 + 4 (c) Q lrn X 4 4 (d) zegtl cg` yxy mr n zibef-i` dlrnn wixt-i` mepilet f Q[X] `di (18.2n-a zwlgzn Q lrn f ly levitd dcy zlrn ik egiked.c \ R-a egiked.char F -a zwlgzn dpi`y dlrnn ziteq zecy zagxd E/F `dz (19.dcixt E/F ik lkl.dcixt dpid ely zixabl` dagxd lk m` (perfect) llkeyn iexw dcy (20 :(ipey`x p o`k) llkeyn `ed m` eraw,mi`ad zecydn cg`.f p (t) (c) ;F p (b) ;Q(t) (a) ;Q (`) E 1 E 2 sexvd mb ik egiked.f dcy ly zeilnxep zeagxd E 1, E 2 dpidz (21?oekp jtidd m`d.f ly zilnxep dagxd epid mepilet ly levit dcy E-y jk M/E/F zeiteq zeagxd lcbnl `nbec epz (22 mepilet ly levit dcy epi` M j`,e lrn mepilet ly levit dcy M,F lrn.f lrn? d`elb zagxd dpid ze`ad zeagxddn in (23 Q( 5 3)/Q (`) Q( 3 2, 2)/Q (a) R(t)/R(t 2 ) (b) R(t)/R(t 3 ) (c) F 7 (t)/f 7 (t 2 ) (d) C( t)/r(t) (e)
3 Gal(M/F ) mr d`elb M/F ik gippe zecy ly lcbn F E M `di (24 z` xiqdl ozip `l ik d`xnd `nbec epz.d`elb E/F ik egiked.ziaihhenew.zeiaihhenewd zgpd ik gipp.e levit dcy mr wixt-i` f F [X] `die 0 oeit`n dcy F `di (25.f ly α yxy lkl E = F (α) ik egiked.ziaihhenew Gal(E/F ) xcqn d`elb zagxd E/F `dz. 1 z` liknd 2 oeit`n dcy F `di (26 :miiwzn mi`ad mi`pzd cg` ik egiked.4 e` ;edylk a F -l E = F ( 4 a) (`).mdylk a, b F -l E = F ( a, b) (a) miipia zagxd oi` ik egiked.a 5 d`elb zxeag mr d`elb zagxd E/F `dz (27.[K : F ] = 2 mr F K E Q(α)/Q ik egiked.q lrn α = 5 + 2 5 ly wixt-i`d mepletd z` e`vn (28.dly d`elb zxeag z` e`vne d`elb zagxd.mipiievnd zecyd lrn mi`ad minepiletd ly d`elb zexeag z` eayg (29 :(icn dlecb dpi` dxeagdyk) miipiad zeagxd bixy z` eayg F 3 lrn X 4 + 6X 2 + X + 1 (`) Q lrn X 6 + X 4 + X 2 + 1 (a) Q lrn X 6 + 1 (b) Q lrn X 4 X 2 + 1 (c) Q lrn Φ 24 (X) (d) C(t) lrn X 3 t (e) R(t) lrn X 3 t (f) F 7 -e F 3,Q( 23),Q lrn X 3 X + 1 (g) Q lrn X 3 3X + 3 (h) Q lrn X 4 4X 2 + 1 (i) Q lrn X 4 3 (`i) F 5 lrn X 4 3 (ai) Q(i) lrn X 4 5 (bi) Q lrn X 5 5X 1 (ci).q lrn 10 i=0 Xi (eh).(dakxdd zlertl qgia) E ly minfitxenehe` zxeag G `dze dcy E `di (30 dveawd m` wxe m` F lrn ixabl` α ik egiked.α E `die F = E G `di.ziteq {σ(α) σ G} Φ 12 (X) z` eayg (31. p 1 k=1 (1 ζk ) = p ik egiked ζ = e 2πi/p -le ipey`x p-l (32
4? Q(e 2πi/42 )/Q dagxdl yi miipia zecy dnk (33? R(t),C(t)-a dcigid iyxy mdn (34.Q(e 2πi/7 )/Q ly zecigid miipiad zeagxd od Q(cos 2π/7)-e Q( 7) ik egiked (35 zlkend 2 dlrnn E/Q dcigi dagxd dpyi ik egiked.ibef-i` ipey`x p `di (36? R-a E lken p miipey`x eli` xear.q(e 2πi/p )-a -le p 1,..., p s mipey miipey`xl :d`ad dcaerd z` oiivp oldly zeiral (37.ϕ( s i=1 pr i i ) = ( ) s i=1 p r i 1 i (p i 1) miiwzn r 1,..., r s 1 miirah miixyt`d eikxr mdn.q ly 2 dlrnn dagxd Q(e 2πi/n )-y jk irah n `di (38?n ly? Q( 3)-a dcigid iyxy mdn (39? ±1-l hxt dcigi iyxy Q( m)-a oi` m minly mixtqn eli` xear (40 ik egiked.ζ n = e 2πi/n ( Q) onqp n 1 irahl (41. Q(ζ n )Q(ζ m ) = Q(ζ lcm(n,m) ), Q(ζ n ) Q(ζ m ) = Q(ζ gcd(n,m) )? Q(ζ n ) Q(ζ m ) izn iyxy ly iteq xtqn wx yi E-a ik egiked.ziteq dagxd E/Q ik gipp (42.dcigi. 1 E-e Gal(E/Q) =Z/4 mr Q ly E d`elb zagxd oi` ik egiked (43 :dpid Gal(E/Q)-y jk Q ly E d`elb zeagxdl ze`nbec epz (44 Z/3 (c) ; Z/11 (b) ;Z/22 (a) ; Z/2 (`) F 1024 /F 2 dagxdd ly miipiad zeagxd lk z` e`vn (45 lkn miwixt-i` minepilet F [X]-a miniiw F iteq dcy lkl ik egiked (46.dlrn? X 2 + 1 = 0 d`eynl oexzt miiw miiteq zecy eli`a (47?F p 3 lrn wixt-i` X 2 + 2X + 2 mepiletd p miipey`x mixtqn el` xear (48 wixt-i` mepilet f F 2 [X] `di.ipey`x 2 n 1 ike irah n > 1 ik gipp (49 dcyd ly ziltkd dxeagd z` zxvei X ly dwlgnd ik egiked.n dlrnn.f 2 [X]/ f
5 ik egiked.dlrn dze`n F q iteq dcy lrn miwixt-i` minepilet f, g eidi (50.miitxenefi` zecy F q [X]/ g -e F q [X]/ f ik egiked.f p lrn F p r ly xvei α `die,miirah r, s eidi,ipey`x p `di (51.mixf r, s m` wxe m` F p s -a wixt-i` xzep irr(α, F p ) dpid F p r lrn X n 1 ly E levitd dcy zlrn ik egiked.ipey`x p `di (52.n q k 1-y jk k ixrfnd irahd yxy α R `di.e levit dcy mr 4 lrnn wixt-i` mepilet f Q[X] `di (53 Gal(E/Q) =A 4 m` ik egiked.ipa α f` Gal(E/Q) =Z/4 m` ik egiked.f ly.ipa epi` α f`.miipa md α ly Q-icenv lk ik egiked.ipa xtqn α `di (54.miiynn miyxey ipy weica mr 4 dlrnn wixt-i` mepilet f Q[X] `di (55 dxeagl d`elb zbvd zgz zitxenefi` dpi` Q lrn f ly d`elb zxeag ik egiked.(s 4 -a zeibefd zexenzd zxeag = ) A 4 zeiteq zexeag eli`?dcy ly ziltk dxeagk zeriten zeiteq zexeag eli` (56?dcy ly zixeaig dxeagk zeriten.zeiteq opi` F p /F p, Q/Q zeagxdd ik egiked (57 E = F (α) miiwnd α E oi`y jk 3 dlrnn E/F dagxdl `nbec epz (58.α 3 F -e :ekixtd e` egiked (59.epnn mipeyd miiwlg zecy Q-l oi` (`) minxeb zltknl C lrn wxtzn Q lrn ziaeig dlrnn wixt-i` mepilet lk (a).mipey mix`pil.r R (mibegk) dxyid dltknl itxenefi` C dcyd (b).α Q(β) if`.ely miyxy α, β C eidie wixt-i` f Q[X] `di (c).cixt epi`y F [X]-a mepilet miiw f` p > 0 oeit`n dcy F m` (d) M/E,E/F m` wxe m` dcixt M/F f` zecy ly lcbn F E M m` (e).zecixt.2014 dlrnn d`elb zagxd C((t))-l yi (f).irah n lkl d`elb Q(sin 2π/n)/Q (g) -y jk irah m miiw f` edylk irah n-l Q(e 2πi/n )-a lkend dcy E m` (h).e = Q(e 2πi/m )