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❚❘×❮◆● ✣❸■ ❍➴❈ ❙× P❍❸▼ ❍⑨ ◆❐■ ✷
❑❍❖❆ ❚❖⑩◆

◆●❯❨➍◆ ❚❍➚ ❍⑨

❍➐◆❍ ❍➴❈ ❊❯❈▲■❉ ❚❘➊◆ ▼➄❚ P❍➃◆●

❑❍➶❆ ▲❯❾◆ ❚➮❚ ◆●❍■➏P ✣❸■ ❍➴❈
❈❤✉②➯♥ ♥❣➔♥❤✿ ❍➻♥❤ ❤å❝

❍⑨ ◆❐■ ✕ ◆➠♠ ✷✵✶✽


❚❘×❮◆● ✣❸■ ❍➴❈ ❙× P❍❸▼ ❍⑨ ◆❐■ ✷
❑❍❖❆ ❚❖⑩◆

◆●❯❨➍◆ ❚❍➚ ❍⑨

❍➐◆❍ ❍➴❈ ❊❯❈▲■❉ ❚❘➊◆ ▼➄❚ P❍➃◆●

❑❍➶❆ ▲❯❾◆ ❚➮❚ ◆●❍■➏P ✣❸■ ❍➴❈
❈❤✉②➯♥ ♥❣➔♥❤✿ ❍➻♥❤ ❤å❝

◆●×❮■ ❍×❰◆● ❉❼◆ ❑❍❖❆ ❍➴❈

P●❙✳❚❙ ◆❣✉②➵♥ ◆➠♥❣ ❚➙♠

❍⑨ ◆❐■ ✕ ◆➠♠ ✷✵✶✽


ớ ỡ


rữợ tr ở ừ õ ỷ ớ ỡ
tợ t ổ tr

rữớ ồ ữ P

ở tr ự ũ ỳ tr tự qỵ
t õ tốt t ử
õ ồ
t ỡ ỳ tọ sỹ trồ ỏ t ỡ s s
tợ t

P ữớ trỹ t ữợ

t t ú ù õ t t õ

ờ q ợ ổ t ự ồ
õ ổ t tr ọ ỳ t sõt t ữ t
ữủ rt ữủ ỳ ỵ õ õ ừ t
ổ õ ừ ỡ
t ỡ

ở t







▲í✐ ❝❛♠ ✤♦❛♥

❉÷î✐ sü ❤÷î♥❣ ❞➝♥ t➟♥ t➻♥❤ ❝õ❛ t❤➛② ❣✐→♦

P●❙✳❚❙ ◆❣✉②➵♥ ◆➠♥❣

❚➙♠ ❦❤â❛ ❧✉➟♥ ❝❤✉②➯♥ ♥❣➔♥❤ ❤➻♥❤ ❤å❝ ✈î✐ ✤➲ t➔✐ ✏❍➻♥❤ ❤å❝ ❊✉❝❧✐❞
tr➯♥ ♠➦t ♣❤➥♥❣✑ ✤÷ñ❝ ❤♦➔♥ t❤➔♥❤ ❜ð✐ q✉→ tr➻♥❤ ❤å❝ t➟♣ ✈➔ ♥❣❤✐➯♥
❝ù✉ ❝õ❛ ❜↔♥ t❤➙♥✱ ❦❤æ♥❣ trò♥❣ ✈î✐ ❜➜t ❝ù ❦❤â❛ ❧✉➟♥ ♥➔♦ ❦❤→❝✳

❚r♦♥❣ ❦❤✐ ♥❣❤✐➯♥ ❝ù✉ ❤♦➔♥ t❤➔♥❤ ✤➲ t➔✐ ♥❣❤✐➯♥ ❝ù✉ ♥➔② ❡♠ ✤➣ t❤❛♠
❦❤↔♦ ♠ët sè t➔✐ ❧✐➺✉ ✤➣ ❣❤✐ tr♦♥❣ ♣❤➛♥ t➔✐ ❧✐➺✉ t❤❛♠ ❦❤↔♦✳

❍➔ ◆ë✐✱ ♥❣➔② ✶✼ t❤→♥❣ ✺ ♥➠♠ ✷✵✶✽
❙✐♥❤ ✈✐➯♥

◆❣✉②➵♥ ❚❤à ❍➔




▼ö❝ ❧ö❝
▲í✐ ❝↔♠ ì♥



▲í✐ ❝❛♠ ✤♦❛♥



▲í✐ ♥â✐ ✤➛✉






▼ët sè ❦❤→✐ ♥✐➺♠ ✈➔ t✐➯♥ ✤➲ tr♦♥❣ ❤➻♥❤ ❤å❝ ❊✉❝❧✐❞



✶✳✶

✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳



✶✳✶✳✶

❙→✉ ❦❤→✐ ♥✐➺♠ ❝ì ❜↔♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳



✶✳✶✳✷

❈→❝ t✐➯♥ ✤➲ ✤÷ñ❝ ♣❤➙♥ t❤➔♥❤ ✺ ♥❤â♠ ✳ ✳ ✳ ✳ ✳ ✳ ✳



❍➺ t✐➯♥ ✤➲ ✈❡❝tì ❝õ❛ ❤➻♥❤ ❤å❝ ❊✉❝❧✐❞ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳




✶✳✷



❍➺ t✐➯♥ ✤➲ ❝õ❛ ❤➻♥❤ ❤å❝ ❊✉❝❧✐❞

▼æ ❤➻♥❤ ✈❡❝tì tr➯♥ ♠➦t ♣❤➥♥❣ ❊✉❝❧✐❞

✶✽

✷✳✶

❍➺ trö❝ tå❛ ✤ë ✣➲ ❝→❝ ✈✉æ♥❣ ❣â❝

✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

✶✽

✷✳✷

❚å❛ ✤ë ❝õ❛ ✤✐➸♠

✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

✶✾

✷✳✸

❚å❛ ✤ë ❝õ❛ ✈❡❝tì


✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

✷✵

✷✳✹

❇✐➸✉ t❤ù❝ ❝õ❛ t➼❝❤ ✈æ ❤÷î♥❣ ❝õ❛ ❤❛✐ ✈❡❝tì t❤❡♦ tå❛ ✤ë ❝õ❛
❝❤ó♥❣

✷✳✺



✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

✷✷

❱➼ ❞ö ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

✷✸

✣÷í♥❣ tr♦♥❣ ♠➦t ♣❤➥♥❣ ❊✉❝❧✐❞



✷✺


❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝
✸✳✶


✣÷í♥❣ t❤➥♥❣ tr♦♥❣ ♠➦t ♣❤➥♥❣ ❊✉❝❧✐❞ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

✷✺

✸✳✶✳✶

P❤÷ì♥❣ tr➻♥❤ t❤❛♠ sè ❝õ❛ ✤÷í♥❣ t❤➥♥❣ ✳ ✳ ✳ ✳ ✳ ✳

✷✺

✸✳✶✳✷

P❤÷ì♥❣ tr➻♥❤ tê♥❣ q✉→t ❝õ❛ ✤÷í♥❣ t❤➥♥❣ ✳ ✳ ✳ ✳ ✳

✷✼

✸✳✶✳✸

❱à tr➼ t÷ì♥❣ ✤è✐ ❝õ❛ ❤❛✐ ✤÷í♥❣ t❤➥♥❣ tr♦♥❣ ♠➦t
♣❤➥♥❣

✸✳✷

◆●❯❨➍◆ ❚❍➚ ❍⑨

✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

✷✽


✸✳✶✳✹

●â❝ ❣✐ú❛ ❤❛✐ ✤÷í♥❣ t❤➥♥❣ tr♦♥❣ ♠➦t ♣❤➥♥❣

✳ ✳ ✳

✸✵

✸✳✶✳✺

❑❤♦↔♥❣ ❝→❝❤ tø ♠ët ✤✐➸♠ ✤➳♥ ♠ët ♠➦t ♣❤➥♥❣ ✳ ✳

✸✷

✣÷í♥❣ ❜➟❝ ❤❛✐ tr♦♥❣ ♠➦t ♣❤➥♥❣ ❊✉❝❧✐❞ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

✸✸

✸✳✷✳✶

✣÷í♥❣ trá♥

✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

✸✸

✸✳✷✳✷

❊❧✐♣


✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

✸✻

✸✳✷✳✸

❍②♣❡❜♦❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

✹✶

✸✳✷✳✹

P❛r❛❜♦❧

✹✻

✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳

❑➳t ❧✉➟♥

✺✵

❚➔✐ ❧✐➺✉ t❤❛♠ ❦❤↔♦

✺✵




▲í✐ ♥â✐ ✤➛✉

✶✳ ▲þ ❞♦ ❝❤å♥ ✤➲ t➔✐
❚♦→♥ ❤å❝ ❧➔ ♠ët ♠æ♥ ❦❤♦❛ ❤å❝ ❝❤✐➳♠ ♠ët ✈à tr➼ ❤➳t sù❝ q✉❛♥ trå♥❣✳
❚♦→♥ ❤å❝ ❧➔ ❝ì sð✱ ❧➔ ♥➲♥ t↔♥❣ ♥❣❤✐➯♥ ❝ù✉ ❝→❝ ♠æ♥ ❦❤♦❛ ❤å❝ ❦❤→❝✳ ❚r♦♥❣
q✉→ tr➻♥❤ ❤å❝ t➟♣✱ tæ✐ ✤÷ñ❝ ♥❣❤✐➯♥ ❝ù✉ ✈➲ ❝❤✉②➯♥ ♥❣➔♥❤ ❤➻♥❤ ❤å❝✱ ♠ët
❜ë ♣❤➟♥ q✉❛♥ trå♥❣ ✈➔ t÷ì♥❣ ✤è✐ ❦❤â tr♦♥❣ ❝❤÷ì♥❣ tr➻♥❤ t♦→♥ ♣❤ê t❤æ♥❣✳
❱î✐ ♠♦♥❣ ♠✉è♥ ✤÷ñ❝ ♥❣❤✐➯♥ ❝ù✉ s➙✉ ✈➲ ❤➻♥❤ ❤å❝ ✈➔ t➻♠ ❤✐➸✉ s➙✉ ❤ì♥
♥ú❛ ✈➲ ❤➻♥❤ ❤å❝ ❊✉❝❧✐❞ tæ✐ ✤➣ ❝❤å♥ ✤➲ t➔✐

✏❍➻♥❤ ❤å❝ ❊✉❝❧✐❞ tr➯♥ ♠➦t

♣❤➥♥❣✑ ❧➔♠ ❦❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣✳
◆ë✐ ❞✉♥❣ ❝❤➼♥❤ ❝õ❛ ❦❤â❛ ❧✉➟♥ ❣ç♠ ❝â ✸ ❝❤÷ì♥❣✿
❈❤÷ì♥❣ ✶✿ ▼ët sè ❦❤→✐ ♥✐➺♠ ✈➔ t✐➯♥ ✤➲ tr♦♥❣ ❤➻♥❤ ❤å❝ ❊✉❝❧✐❞
❈❤÷ì♥❣ ✷✿ ▼æ ❤➻♥❤ ✈❡❝tì tr➯♥ ♠➦t ♣❤➥♥❣ ❊✉❝❧✐❞
❈❤÷ì♥❣ ✸✿ ✣÷í♥❣ tr♦♥❣ ♠➦t ♣❤➥♥❣ ❊✉❝❧✐❞

✷✳ ▼ö❝ ✤➼❝❤ ♥❣❤✐➯♥ ❝ù✉
❑❤â❛ ❧✉➟♥ ♥❤➡♠ ♠ö❝ ✤➼❝❤✿ ●✐ó♣ s✐♥❤ ✈✐➯♥ ❝â ❝→✐ ♥❤➻♥ s➙✉ ❤ì♥ ✈➲
❤➻♥❤ ❤å❝ ❊✉❝❧✐❞✳




❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨

✸✳ ◆❤✐➺♠ ✈ö ♥❣❤✐➯♥ ❝ù✉
❚r➻♥❤ ❜➔② ❝ì ❜↔♥ ✈➲ ❤➻♥❤ ❤å❝ ❊✉❝❧✐❞ tr➯♥ ♠➦t ♣❤➥♥❣✳


✹✳ ✣è✐ t÷ñ♥❣ ✈➔ ♣❤↕♠ ✈✐ ♥❣❤✐➯♥ ❝ù✉
✲ ✣è✐ t÷ñ♥❣ ♥❣❤✐➯♥ ❝ù✉✿ ❍➻♥❤ ❤å❝ ❊✉❝❧✐❞ tr➯♥ ♠➦t ♣❤➥♥❣✳
✲ P❤↕♠ ✈✐ ♥❣❤✐➯♥ ❝ù✉✿ ❈→❝ t➔✐ ❧✐➺✉ t❤❛♠ ❦❤↔♦ ❧✐➯♥ q✉❛♥ ✤➳♥ ❤➻♥❤
❤å❝ ❊✉❝❧✐❞✳

✺✳ P❤÷ì♥❣ ♣❤→♣ ♥❣❤✐➯♥ ❝ù✉
❚ê♥❣ ❤ñ♣ ❦✐➳♥ t❤ü❝ t❤✉ ♥❤➟♣ ✤÷ñ❝ q✉❛ ♥❤ú♥❣ t➔✐ ❧✐➺✉ ❧✐➯♥ q✉❛♥ ✤➳♥
✤➲ t➔✐ ✈➔ sû ❞ö♥❣ ❝→❝ ♣❤÷ì♥❣ ♣❤→♣ ♥❣❤✐➯♥ ❝ù✉ ❝õ❛ ❤➻♥❤ ❤å❝✳

✻✳ ✣â♥❣ ❣â♣ ❝õ❛ ✤➲ t➔✐
❳➙② ❞ü♥❣ ❦❤â❛ ❧✉➟♥ t❤➔♥❤ ♠ët t➔✐ ❧✐➺✉ tê♥❣ q✉❛♥ tèt ❝❤♦ s✐♥❤ ✈✐➯♥
✈î✐ ✤➲ t➔✐ ✏❍➻♥❤ ❤å❝ ❊✉❝❧✐❞ tr➯♥ ♠➦t ♣❤➥♥❣✑✳
❉♦ ❧➔ ❧➛♥ ✤➛✉ t✐➯♥ t❤ü❝ t➟♣ ♥❣❤✐➯♥ ❝ù✉✱ t❤í✐ ❣✐❛♥ ❝â ❤↕♥ ✈➔ ♥➠♥❣ ❧ü❝
❜↔♥ t❤➙♥ ❝á♥ ❤↕♥ ❝❤➳ ♥➯♥ ❜➔✐ ♥❣❤✐➯♥ ❝ù✉ ♥➔② ❦❤â tr→♥❤ ❦❤ä✐ ♥❤ú♥❣ s❛✐
sât✳ ❊♠ r➜t ♠♦♥❣ ♥❤➟♥ ✤÷ñ❝ ♥❤ú♥❣ ✤â♥❣ ❣â♣✱ þ ❦✐➳♥ ❝õ❛ ❝→❝ t❤➛②✱ ❝æ
❣✐→♦ ✈➔ ❜↕♥ ✤å❝ ✤➸ ✤➲ t➔✐ ✤÷ñ❝ ❤♦➔♥ ❝❤➾♥❤ ✈➔ ✤↕t ❦➳t q✉↔ ❝❛♦ ❤ì♥✳
❊♠ ①✐♥ ❝❤➙♥ t❤➔♥❤ ❝↔♠ ì♥✦




❈❤÷ì♥❣ ✶
▼ët sè ❦❤→✐ ♥✐➺♠ ✈➔ t✐➯♥ ✤➲ tr♦♥❣
❤➻♥❤ ❤å❝ ❊✉❝❧✐❞
❈❤÷ì♥❣ ♥➔② tr➻♥❤ ❜➔② sì ❧÷ñ❝ ✈➲ ❦❤→✐ ♥✐➺♠ ✈➔ t✐➯♥ ✤➲ tr♦♥❣ ❤➻♥❤
❤å❝ ❊✉❝❧✐❞✳ ❈→❝ ❦✐➳♥ t❤ù❝ ♥➔② ♣❤ö❝ ✈ö ❝❤♦ ✈✐➺❝ ①➙② ❞ü♥❣ ❝→❝ ♠æ ❤➻♥❤
✈❡❝tì ✈➔ ✤÷í♥❣ tr♦♥❣ ♠➦t ♣❤➥♥❣ ❊✉❝❧✐❞ ð ❝❤÷ì♥❣ s❛✉✳ ❈→❝ ❦✐➳♥ t❤ù❝ ❝õ❛
❝❤÷ì♥❣ ✤÷ñ❝ ✈✐➳t ❞ü❛ tr➯♥ ❝→❝ t➔✐ ❧✐➺✉ ❬✶❪✱ ❬✹❪✱ ❬✺❪✳

✶✳✶ ❍➺ t✐➯♥ ✤➲ ❝õ❛ ❤➻♥❤ ❤å❝ ❊✉❝❧✐❞

✶✳✶✳✶

❙→✉ ❦❤→✐ ♥✐➺♠ ❝ì ❜↔♥

✣✐➸♠✱ ✤÷í♥❣ t❤➥♥❣✱ ♠➦t ♣❤➥♥❣✱ t❤✉ë❝✱ ð ❣✐ú❛✱ t♦➔♥ ✤➥♥❣✳

✶✳✶✳✷

❈→❝ t✐➯♥ ✤➲ ✤÷ñ❝ ♣❤➙♥ t❤➔♥❤ ✺ ♥❤â♠

◆❤â♠ ■ ✭❈→❝ t✐➯♥ ✤➲ ❧✐➯♥ ✧t❤✉ë❝✧✮
■✶✿ ❈â ➼t ♥❤➜t ❤❛✐ ✤✐➸♠ t❤✉ë❝ ♠é✐ ✤÷í♥❣ t❤➥♥❣✳
■✷✿ ❈â ♠ët ✈➔ ❝❤➾ ♠ët ✤÷í♥❣ t❤➥♥❣ t❤✉ë❝ ❤❛✐ ✤✐➸♠ ♣❤➙♥ ❜✐➺t ❝❤♦
tr÷î❝✳




❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨

■✸✿ ❈â ➼t ♥❤➜t ❜❛ ✤✐➸♠ ❦❤æ♥❣ ❝ò♥❣ t❤✉ë❝ ♠ët ✤÷í♥❣ t❤➥♥❣✳
■✹✿ ❈â ♠ët ✈➔ ❝❤➾ ♠ët ♠➦t ♣❤➥♥❣ t❤✉ë❝ ❜❛ ✤✐➸♠ ❦❤æ♥❣ t❤➥♥❣ ❤➔♥❣✭
❦❤æ♥❣ ❝ò♥❣ t❤✉ë❝ ♠ët ✤÷í♥❣ t❤➥♥❣✮✳ ▼➦t ♣❤➥♥❣ ❝â ➼t ♥❤➜t ♠ët ✤✐➸♠✳
■✺✿ ✣÷í♥❣ t❤➥♥❣ ❝â ❤❛✐ ✤✐➸♠ t❤✉ë❝ ♠ët ♠➦t ♣❤➥♥❣ t❤➻ ♠å✐ ✤✐➸♠ ❝õ❛
✤÷í♥❣ t❤➥♥❣ ✤➲✉ t❤✉ë❝ ♠➦t ♣❤➥♥❣ ✤â✳
■✻✿ ❍❛✐ ♠➦t ♣❤➥♥❣ ♣❤➙♥ ❜✐➺t ❝â ♠ët ✤✐➸♠ ❝❤✉♥❣ t❤➻ ❝á♥ ❝â ♠ët ✤✐➸♠
❝❤✉♥❣ t❤ù ❤❛✐ ❦❤→❝ ♥ú❛✳
■✼✿ ❚ç♥ t↕✐ ❜è♥ ✤✐➸♠ ❦❤æ♥❣ ❝ò♥❣ t❤✉ë❝ ♠ët ♠➦t ♣❤➥♥❣✳

◆❤â♠ ■■ ✭❈→❝ t✐➯♥ ✤➲ ✈➲ t❤ù tü✮
■■✶✿ ◆➳✉ ✤✐➸♠ ❇ ð ❣✐ú❛ ❤❛✐ ✤✐➸♠ ❆ ✈➔ ❈ t❤➻ ❆✱ ❇✱ ❈ ❧➔ ❜❛ ✤✐➸♠ ♣❤➙♥
❜✐➺t ❝ò♥❣ t❤✉ë❝ ♠ët ✤÷í♥❣ t❤➥♥❣ ✈➔ ✤✐➸♠ ❇ ð ❣✐ú❛ ❤❛✐ ✤✐➸♠ ❈ ✈➔ ❆✳
■■✷✿ ❇➜t ❦ý ❤❛✐ ✤✐➸♠ ❆ ✈➔ ❈ ♥➔♦ ❝ô♥❣ ❝â ♠ët ✤✐➸♠ ❇ s❛♦ ❝❤♦ ❈ ð
❣✐ú❛ ❆ ✈➔ ❇✳
■■✸✿ ❚r♦♥❣ ❜❛ ✤✐➸♠ ❝ò♥❣ t❤✉ë❝ ♠ët ✤÷í♥❣ t❤➥♥❣ ❝â ❦❤æ♥❣ q✉→ ♠ët
✤✐➸♠ ð ❣✐ú❛ ❤❛✐ ✤✐➸♠ ❦✐❛✳
■■✹✿ ❈❤♦ ❜❛ ✤✐➸♠ ❆✱ ❇ ✈➔ ❈ ❦❤æ♥❣ ❝ò♥❣ t❤✉ë❝ ♠ët ✤÷í♥❣ t❤➥♥❣ ✈➔
❝❤♦ ✤÷í♥❣ t❤➥♥❣ ❛ ❦❤æ♥❣ ✤✐ q✉❛ ❤❛✐ ✤✐➸♠ ♥➔♦ tr♦♥❣ ❜❛ ✤✐➸♠ ✤â✳ ❑❤✐
✤â ♥➳✉ ✤÷í♥❣ t❤➥♥❣ ❛ t❤✉ë❝ ♠ët ✤✐➸♠ ð ❣✐ú❛ ❆ ✈➔ ❇ t❤➻ ❦❤✐ ✤â ♥â ❝á♥
t❤✉ë❝ ♠ët ✤✐➸♠ ð ❣✐ú❛ ❇ ✈➔ ❈ ❤♦➦❝ ð ❣✐ú❛ ❈ ✈➔ ❆✳
◆❤â♠ ■■■ ✭❈→❝ t✐➯♥ ✤➲ ✈➲ t♦➔♥ ✤➥♥❣✮
■■■✶✿ ❈❤♦ ✤✐➸♠ ❆ t❤✉ë❝ ✤÷í♥❣ t❤➥♥❣ ❛✳ ◆❣♦➔✐ r❛ ❝❤♦ ❈❉ ❧➔ ♠ët
✤♦↕♥ t❤➥♥❣ ❜➜t ❦➻ ✭✤♦↕♥ t❤➥♥❣ ❤✐➸✉ ❧➔ t➟♣ ❤ñ♣ ❣ç♠ ❤❛✐ ✤✐➸♠✮✳ ❑❤✐
✤â ❤❛✐ ✤✐➸♠

B1 , B2

t❤✉ë❝ ❛ s❛♦ ❝❤♦

AB1 = CD, AB2 = CD.

AB1 , AB2

❱î✐ ♠é✐ ✤♦↕♥ t❤➥♥❣

❜➡♥❣ ✤♦↕♥

AB


CD✳

t❛ ✤➲✉ ❝â

❑➼ ❤✐➺✉

AB = BA.

■■■✷✿ ◗✉❛♥ ❤➺ ❣✐ú❛ ❝→❝ ✤♦↕♥ t❤➥♥❣ ❝â t➼♥❤ ❝❤➜t ♣❤↔♥ ①↕✱ ✤è✐ ①ù♥❣✱




❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨

❜➢❝ ❝➛✉✱ ❝ö t❤➸ ❧➔✿
✶✳

AB = BA

✷✳ ◆➳✉

AB = CD

✸✳ ◆➳✉

AB = CD, CD = EF


■■■✸✿ ❈❤♦ ✤✐➸♠

A

✈➔

C✳

B

❑❤✐ ✤â ♥➳✉

t❤➻

t❤➻

AB = EF

AB = A B , AC = A C
ABC ✈➔ A B C

❝â

t❤➻

ð ❣✐ú❛ ❤❛✐ ✤✐➸♠

BC = B C .

AB = A B , AC = A C , BAC =


BAC = A B C , ACB = A C B

t❤➻

B

ð ❣✐ú❛ ❤❛✐ ✤✐➸♠ ❆ ✈➔ ❈✱ ✤✐➸♠

■■■✹✿ ◆➳✉ ❤❛✐ t❛♠ ❣✐→❝

BAC

CD = AB

✈➔

BC = B C .

◆❤â♠ ■❱ ✭◆❤â♠ ❝→❝ t✐➯♥ ✤➲ ❧✐➯♥ tö❝✮
■❱✶✿ ❱î✐ ❜➜t ❦➻ ❤❛✐ ✤♦↕♥ t❤➥♥❣
♥ s❛♦ ❝❤♦♥

AB

✈➔

CD ❜❛♦ ❣✐í ❝ô♥❣ ❝â sè tü ♥❤✐➯♥

AB > CD.


■❱✷✿ ●✐↔ sû tr➯♥ ✤÷í♥❣ t❤➥♥❣ ❛ ❝❤♦ ♠ët ❞➣② ✈æ ❤↕♥ ❝→❝ ✤♦↕♥ t❤➥♥❣

A1 B1 , A2 B2 , . . . An Bn , ...

s❛♦ ❝❤♦ ♠é✐ ✤♦↕♥ t❤➥♥❣ ♥➡♠ tr♦♥❣ ✤♦↕♥ t❤➥♥❣

tr÷î❝ ♥â ✈➔ ❜➜t ❦➻ ✤♦↕♥ t❤➥♥❣
♥❤✐➯♥ ♥ ✤➸

An Bn < CD✳

CD

♥➔♦ ❝❤♦ tr÷î❝ ❜❛♦ ❣✐í ❝ô♥❣ ❝â sè tü

❑❤✐ ✤â tr➯♥ ✤÷í♥❣ t❤➥♥❣

a

❝â ♠ët ✤✐➸♠

X

t❤✉ë❝ ♠å✐ ✤♦↕♥ t❤➥♥❣ ❝õ❛ ❞➣② ✤➣ ❝❤♦✳
◆❤â♠ ❱ ✭❚✐➯♥ ✤➲ ✈➲ ✤÷í♥❣ t❤➥♥❣ s♦♥❣ s♦♥❣✮
❱✿ ◗✉❛ ♠é✐ ✤✐➸♠
✤÷í♥❣ t❤➥♥❣
❝❤✉♥❣ ✈î✐


b

A

❦❤æ♥❣ t❤✉ë❝ ✤÷í♥❣ t❤➥♥❣

❝ò♥❣ ♥➡♠ tr♦♥❣ ♠➦t ♣❤➥♥❣

a

❝â ❦❤æ♥❣ q✉→ ♠ët

P = (A, a)

❦❤æ♥❣ ❝â ✤✐➸♠

a✳

✶✳✷ ❍➺ t✐➯♥ ✤➲ ✈❡❝tì ❝õ❛ ❤➻♥❤ ❤å❝ ❊✉❝❧✐❞
✣à♥❤ ♥❣❤➽❛ ✶✳✷✳✶✳ ❱❡❝tì ❧➔ ♠ët ❝➦♣ ✤✐➸♠
❦➼ ❤✐➺✉ ❧➔

−−→
XY ✱

tr♦♥❣ ✤â

X

(X; Y )


✤÷ñ❝ ❣å✐ ❧➔ ✤✐➸♠ ✤➛✉✱

❝✉è✐ ❝õ❛ ✈❡❝tì✳



s➢♣ t❤ù tü ✈➔ ✤÷ñ❝

Y

✤÷ì❝ ❣å✐ ❧➔ ✤✐➸♠


❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨

❱❡❝tì ❝â ✤✐➸♠ ✤➛✉ ✈➔ ❝✉è✐ trò♥❣ ♥❤❛✉ ✤÷ñ❝ ❣å✐ ❧➔ ✈❡❝tì ❦❤æ♥❣ ✈➔ ❦➼
❤✐➺✉ ❧➔



0✳

❑❤✐ t❛ ❦❤æ♥❣ q✉❛♥ t➙♠ ✤✐➸♠ ✤➛✉ ✈➔ ✤✐➸♠ ❝✉è✐ ❝õ❛ ✈❡❝tì✱ ✈❡❝tì ❝á♥
✤÷ñ❝ ❦➼ ❤✐➺✉ ❧➔✿


− − →



a , b ,→
x ,−
y , ....

✣à♥❤ ♥❣❤➽❛ ✶✳✷✳✷✳ ❍❛✐ ✈❡❝tì
♥❤❛✉ ♥➳✉ ✤÷í♥❣ t❤➥♥❣

XY

−−→
XY

✈➔

−→
ZT

✤÷ñ❝ ❣å✐ ❧➔ ❝ò♥❣ ♣❤÷ì♥❣ ✈î✐

✈➔ ✤÷í♥❣ t❤➥♥❣

ZT

s♦♥❣ s♦♥❣ ❤♦➦❝ trò♥❣

♥❤❛✉✳

✣à♥❤ ♥❣❤➽❛ ✶✳✷✳✸✳ ❍❛✐ ✈❡❝tì ❝ò♥❣ ♣❤÷ì♥❣


−−→
−→
XY ✈➔ ZT ✤÷ñ❝ ❣å✐ ❧➔ ❝ò♥❣

❤÷î♥❣ ✈î✐ ♥❤❛✉ ♥➳✉ ❝❤ó♥❣ ❝â ❝ò♥❣ ❤÷î♥❣ ✤✐ tø ✤✐➸♠ ✤➛✉ ✤➳♥ ✤✐➸♠ ❝✉è✐✱
♥❣÷ñ❝ ❧↕✐ ✤÷ñ❝ ❣å✐ ❧➔ ❤❛✐ ✈❡❝tì ♥❣÷ñ❝ ❤÷î♥❣ ✈î✐ ♥❤❛✉✳

✣à♥❤ ♥❣❤➽❛ ✶✳✷✳✹✳ ✣ë ❞➔✐ ✤♦↕♥ t❤➥♥❣

XY

✈➔ ✤÷ñ❝ ❦➼ ❤✐➺✉ ❧➔

❙è t❤ü❝

√→

x2

✤÷ñ❝ ❣å✐ ❧➔ ✤ë ❞➔✐ ❝õ❛ ✈❡❝tì

−−→
|XY |

✤÷ñ❝ ❣å✐ ❧➔

♠æ✤✉♥

√→



x 2 = |→
x|


|→
x |✳ ❑❤✐ ✤â


❱❡❝tì x ✤÷ñ❝ ❣å✐

❤✐➺✉ ❧➔

XY

✭✤ë ❞➔✐✮ ❝õ❛ ✈❡❝tì

❧➔ ✈❡❝tì ✤ì♥ ✈à ♥➳✉


|→
x|=1

❚➼♥❤ ❝❤➜t✿
✐✳


|→
x|≥0


✈➔





|→
x|=0⇔→
x = 0,
✶✵


∀→
x

❜➜t ❦➻❀



x

✈➔ ✤÷ñ❝ ❦➼


❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨





|→
x 2| = →
x 2 , ∀→
x ❜➜t ❦➻❀





✐✐✐✳ |λ x | = |λ|.| x |,
∀→
x ❜➜t ❦➻✱∀λ ∈ R;

−→


− →



✐✈✳ | x y | ≤ | x || y |,
∀→
x ,→
y ❜➜t ❦➻❀
✐✐✳

✈✳






|→
x +→
y | ≤ |→
x | + |→
y |,



∀→
x ,→
y

✣à♥❤ ♥❣❤➽❛ ✶✳✷✳✺✳ ❍❛✐ ✈❡❝tì

−−→
XY

❜➜t ❦➻✳

✈➔

−→
ZT

✤÷ñ❝ ❣å✐ ❧➔ ❜➡♥❣ ♥❤❛✉ ♥➳✉


❝❤ó♥❣ ❝ò♥❣ ❤÷î♥❣ ✈➔ ❝â ✤ë ❞➔✐ ❜➡♥❣ ♥❤❛✉✱ ❦➼ ❤✐➺✉ ❧➔

✣à♥❤ ♥❣❤➽❛ ✶✳✷✳✻✳ ❈❤♦ ❤❛✐ ✈❡❝tì
❦➼ ❤✐➺✉ ❧➔




x +→
y

−−→ −→
XY = ZT ✳




x ✈➔ →
y tê♥❣ ❝õ❛ ❝❤ó♥❣ ❧➔ ♠ët ✈❡❝tì✱

✈➔ ✤÷ñ❝ ①→❝ ✤à♥❤ ♥❤÷ s❛✉✿

X ❜➜t ❦➻ t❛ ①→❝ ✤à♥❤ ✤÷ñ❝ ✤✐➸♠ Y
−−→ →
−→ −
−−→


XY = −
x ,Y Z = →

y ✳ ❑❤✐ ✤â t❛ ❝â →
x +→
y = XZ ✳
❚ø ♠ët ✤✐➸♠

❱➟② ✈î✐ ❜❛ ✤✐➸♠

X, Y

✈➔

Z

✈➔ ✤✐➸♠

❜➜t ❦➻ tr♦♥❣ ♠➦t ♣❤➥♥❣ t❛ ❝â✿

Z

s❛♦ ❝❤♦

−−→ −→
XY + Y Z =

−−→
XZ ✳






x +→
y =→
y +→
x❀






(→
x +→
y)+→
z =→
x + (→
y +→
z )❀

✐✳ ❚➼♥❤ ❝❤➜t ❣✐❛♦ ❤♦→♥✿
✐✐✳ ❚➼♥❤ ❝❤➜t ❦➳t ❤ñ♣✿


− →



0✿−
x + 0 =→
x❀









✈î✐ ✈❡❝tì ✤è✐✿ x + (− x ) = 0 ✱ tr♦♥❣ ✤â (− x )




❝õ❛ ✈❡❝tì x ✈➔ ❝â ✤ë ❞➔✐ ❜➡♥❣ ✤ë ❞➔✐ ✈❡❝tì a

✐✐✐✳ ❚➼♥❤ ❝❤➜t ❝ë♥❣ ✈î✐
✐✈✳ ❚➼♥❤ ❝❤➜t ❝ë♥❣
✤÷ñ❝ ❣å✐ ❧➔ ✈❡❝tì ✤è✐

♥❤÷♥❣ ❤÷î♥❣ ♥❣÷ñ❝ ❝❤✐➲✉ ✈î✐ ✈❡❝tì



a✳

✶✶


õ tốt ồ




tỡ


k
x


|
x | = ||.|
x|

tỡ




x



=0





x


t t õ



x

số tỹ



t ừ ú ởt

ữủ ữ s

ũ ữợ

>0

ữủ ữợ

< 0






0.
x = 0


t t









(
x +
y ) =
x +
y



( + à)
x =
x + à
x



x ) = (à)
x


1.

x =
x





a1 ,
a2 , ã ã ã
an k số p1 , p2 , ..., pk






õ t ồ p1 . a1 + p2 . a2 + ã ã ã + pn .an ởt tờ ủ t t tỡ




a ,
a ,ããã
a số p , p , ã ã ã , p số ừ tờ ủ t t


1




2

k

1

tỡ

2

k

pi R
tỡ

số

k





a1 ,
a2 , ã ã ã ,
ak

p1 , p2 , ã ã ã , pk

ồ ử tở t t tỗ t


ổ ỗ tớ

0

s




p1 .
a1 + p2 .
a2 + ã ã ã + pk .
ak = 0.
r trữớ ủ ữủ tỡ
t t õ tỡ






a1 ,
a2 , ã ã ã



a ,
a ,ããã
1


2


,
ak

,
a

ồ ở

k ồ ở


❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨

t✉②➳♥ t➼♥❤ t❤➻ t❛ ❝â ✤➥♥❣ t❤ù❝




p1 .→
a1 + p2 .→
a2 + · · · + pk .→
ak = 0

❦❤✐


p1 = p2 = · · · = pk = 0.
✣à♥❤ ❧➼ ✶✳ ❈→❝ ✈❡❝tì





a1 , →
a2 , · · · , →
ak (k > 1) ♣❤ö t❤✉ë❝ t✉②➳♥ t➼♥❤ ❦❤✐

✈➔ ❝❤➾ ❦❤✐ ❝â ➼t ♥❤➜t ♠ët tr♦♥❣ ❝→❝ ✈❡❝tì ➜② ❧➔ tê ❤ñ♣ t✉②➳♥ t➼♥❤ ❝õ❛ ❝→❝
✈❡❝tì ❝á♥ ❧↕✐✳
❈❤ù♥❣ ♠✐♥❤ ✤à♥❤ ❧þ ✶✿
✣✐➲✉ ❦✐➺♥ ❝➛♥✿ ●✐↔ sû ❝→❝ ✈❡❝tì





a1 , →
a2 , · · · , →
ak

♣❤ö t❤✉ë❝ t✉②➳♥ t➼♥❤

t❛ ❝â✿







p→
a1 + p→
a2 + · · · p k →
ak = 0
tr♦♥❣ ✤â ❝â ➼t ♥❤➜t ♠ët sè tr♦♥❣ ❜ë sè

pk = 0

p1 , p2 , · · · , pk

❦❤→❝

0✳

●✐↔ sû

s✉② r❛✿



p1 →
p2 −
pk−1 −−→ →

a1 − →
a2 − · · · −

ak−1 = −
ak .
pk
pk
pk



→ →

p1 .→
a1 + p2 .→
a2 + ... + pk−1 .−
a−
k−1 = ak ✳


→ →

p1 .→
a1 + p2 .→
a2 + ... + pk−1 .−
a−
k−1 − ak = 0 tr♦♥❣

✣✐➲✉ ❦✐➺♥ ✤õ✿ ●✐↔ sû
❚ø ✤â t❛ ❝â✿
t❤ù

✤â ❤➺ sè


k = 0✳




a1 , →
a2 , ..., →
ak (k > 1) ♣❤ö t❤✉ë❝ t✉②➳♥ t➼♥❤✳

− →



◆➳✉ ❝→❝ ✈❡❝tì a , a , ..., a (k > 1) ✤ë❝ ❧➟♣ t✉②➳♥

❱➟② ❝→❝ ✈❡❝tì

❍➺ q✉↔ ✶✳

1

2

k

t➼♥❤ t❤➻

❜➜t ❦➻ ✈❡❝tì ♥➔♦ tr♦♥❣ t➟♣ ❤ñ♣ ❝→❝ ✈❡❝tì ➜② ❝ô♥❣ ❦❤æ♥❣ t❤➸ ❧➔ ♠ët tê
❤ñ♣ t✉②➳♥ t➼♥❤ ❝õ❛ ❝→❝ ✈❡❝tì ❝á♥ ❧↕✐✳


✣à♥❤ ❧þ ✷✳ ✣✐➲✉ ❦✐➺♥ ❝➛♥ ✈➔ ✤õ ✤➸ ❤❛✐ ✈❡❝tì ♣❤ö t❤✉ë❝ t✉②➳♥ t➼♥❤ ❧➔
❝❤ó♥❣ ❝ò♥❣ ♣❤÷ì♥❣✳
❈❤ù♥❣ ♠✐♥❤ ✤à♥❤ ❧þ ✷✿
✣✐➲✉ ❦✐➺♥ ❝➛♥✿ ●✐↔ sû



a1

✈➔



a2

♣❤ö t❤✉ë❝ t✉②➳♥ t➼♥❤✳

✶✸


❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨







a1 = p1 →
a2 ❤♦➦❝ →
a2 = p2 .→
a1




◆❤÷ ✈➟② ❤❛✐ ✈❡❝tì a1 ✈➔ a2 ❝ò♥❣ ♣❤÷ì♥❣✳




✣✐➲✉ ❦✐➺♥ ✤õ✿ ◆➳✉ ❤❛✐ ✈❡❝tì a ✈➔ a ❝ò♥❣ ♣❤÷ì♥❣✱

❚❤❡♦

✤à♥❤ ❧➼ ✶ t❛ ❝â✿

1

2




a1 = p.→
a2 ❤♦➦❝ ❝â




a = 0 ✈➔ →
a = 0.

r➡♥❣ ❝â sè ♣ s❛♦ ❝❤♦
❝➛♥ ①➨t tr÷í♥❣ ❤ñ♣
●å✐



e1

✈➔



e2

✈➔



a2

p

s❛♦ ❝❤♦





a1 = p.→
a2

✳ ❚❛ ❝❤➾

2

❧➔ ❝→❝ ✈❡❝tì ✤ì♥ ✈à ❝ò♥❣ ❤÷î♥❣

❝ò♥❣ ♣❤÷ì♥❣ ♥➯♥



a1

1



t❛ s➩ ❝❤ù♥❣ ♠✐♥❤




e1 = ±→
e2

✭❞➜✉ ✰ ❦❤✐




a1

✈➔



a2



a1

✈➔



a2 ✳

❱➻



a1

❝ò♥❣ ❤÷î♥❣✱ ❞➜✉

✈➔




a2



❦❤✐

♥❣÷ñ❝ ❤÷î♥❣✮✳

❚❛ ❝â








a1 = |→
a1 |.→
e1 ; →
a2 = |→
a2 |.→
e2
❚❛ s✉② r❛

1 →
1 →







e1 = →
a
,
e
=
a2
1
2



| a1 |
| a2 |
❱➻




e1 = ±→
e2

♥➯♥

1→
1 →



a1 = ± →
a2



a1
| a2 |
❤❛②


|→
a1 | →



a1 = ± →
a2

| a2 |

✣✐➲✉ ❝➛♥ ❝❤ù♥❣ ♠✐♥❤✳

❍➺ q✉↔ ✷✳ ❍❛✐ ✈❡❝tì ✤ë❝ ❧➟♣ t✉②➳♥ t➼♥❤ ❦❤✐ ✈➔ ❝❤➾ ❦❤✐ ❝❤ó♥❣ ❦❤æ♥❣
❝ò♥❣ ♣❤÷ì♥❣✳

✣à♥❤ ❧➼ ✸✿ ❈❤♦ ❤❛✐ ✈❡❝tì ❦❤æ♥❣ ❝ò♥❣ ♣❤÷ì♥❣
✈❡❝tì




a

♥➔♦ ✤ç♥❣ ♣❤➥♥❣ ✈î✐



e1

✈➔



e2

✈➔



e2 ✳

❇➜t ❦➻ ♠ët

❝ô♥❣ ❝â t❤➸ ❦❤❛✐ tr✐➸♥ t❤❡♦ ❝→❝

✈❡❝tì ➜②✱ ♥❣❤➽❛ ❧➔






a = x1 →
e1 + x2 →
e2

✶✹



e1

(1)


õ tốt ồ



sỹ tr tr t
ự ỵ ứ ởt

O

tũ ỵ t ỹ tỡ



OE1 =
e1 , OE2 =

e2 , OA =
a

tt tỡ


A





e1 ,
e2 ,
a ỗ ố O, A1 , A2

ũ tở ởt t

s ợ ừ tỡ



OE2 , OE1

A

ỹ ữớ t s

t ừ tỡ



OE2 , OE1

t

A2 , A1

tỡ


OE1




OA1

ũ ữỡ




OE1 = 0




OA1 =



x1 OE1
ữỡ tỹ t õ



OA2 = x2 OE2

õ




OA = OA1 + OA2 = x1 OE1 + x2 OE2






a = x1
e1 + x2
e2
ự tr tr t t sỷ
tr t ỏ õ tr s





a = y1

e 1 + y2
e2


(2)


❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨

❚rø ✭✶✮ ✈➔ ✭✷✮ ✈➳ ✈î✐ ✈➳ t❛ ✤÷ñ❝ ✿





0 = (x1 − y1 )→
e1 + (x2 − y2 )→
e2 (3)
❱➻ ❝→❝ ✈❡❝tì



e1

✈➔




e2

❦❤æ♥❣ ❝ò♥❣ ♣❤÷ì♥❣ ♥➯♥ t❤❡♦

❤➺ q✉↔ ✷ ❝❤ó♥❣

✤ë❝ ❧➟♣ t✉②➳♥ t➼♥❤✳ ❚ø ✭✸✮ t❛ s✉② r❛✿





x =y
 x −y =0
1
1
1
1



 x 2 = y2
 x2 − y2 = 0
✣✐➲✉ ❝➛♥ ❝❤ù♥❣ ♠✐♥❤✳

✣à♥❤ ♥❣❤➽❛ ✶✳✷✳✾✳ ❚➼❝❤ ✈æ ❤÷î♥❣ ❝õ❛ ❤❛✐ ✈❡❝tì





x ✈➔ →
y ❧➔ ♠ët sè ❜➡♥❣

t➼❝❤ ♠æ✤✉♥ ❝õ❛ ❤❛✐ ✈❡❝tì ✈î✐ ❝♦s✐♥ ❣â❝ ①❡♠ ❣✐ú❛ ❝õ❛ ❤❛✐ ✈❡❝tì ➜②✳ ❑➼




x .→
y✳







x ✈➔ →
y t❤➻✿ →
x .→
y = |→
x |.|→
y |. cos ϕ

❤✐➺✉ t➼❝❤ ✈æ ❤÷î♥❣ ❝õ❛ ❤❛✐ ✈❡❝tì ❧➔
●å✐

ϕ

❧➔ ❣â❝ ❣✐ú❛ ❤❛✐ ✈❡❝tì


▼ët sè t➼♥❤ ❝❤➜t ❝õ❛ t➼❝❤ ✈æ ❤÷î♥❣ ❝õ❛ ❤❛✐ ✈❡❝tì✿








x .→
y =→
y .→
x , ∀→
x ,→
y❀

− →
− →


− →
− →
− →

✐✐✳ x .( y + y ) = x . y + x . y ,
✐✳





∀→
x ,→
y1 , →
y2 ;

− →


−→


− →



✐✐✐✳ (λ x ) y = λ( x y ) = x (λ y ),
∀→
x ,→
y ✱λ ∈ R;



− →


− →





✐✈✳ x . x ≥ 0, x . x = 0 ⇔ x = 0 ,
∀→
x✳
1

2

1

2

✣à♥❤ ♥❣❤➽❛ ✶✳✷✳✶✵✳ ●✐→ trà

ϕ ∈ [0; π]

s❛♦ ❝❤♦




x→
y
cos ϕ = →


| x ||→
y|
✤÷ñ❝ ❣å✐ ❧➔ ❣â❝ ❣✐ú❛ ❤❛✐ ✈❡❝tì
✈➔




x

✈➔



y ✮✳

✶✻



y

✭❦❤æ♥❣ ♣❤ö t❤✉ë❝ ✈➔♦ ✈❡❝tì



x


❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨

❍➺ q✉↔ ✸✳ ❍❛✐ ✈❡❝ tì ✈✉æ♥❣ ❣â❝ ✈î✐ ♥❤❛✉ ♥➳✉ t➼❝❤ ✈æ ❤÷î♥❣ ❝õ❛
❝❤ó♥❣ ❜➡♥❣ ✵ tù❝ ❧➔







x ⊥→
y ⇔→
x .→
y = 0✳

✶✼


❈❤÷ì♥❣ ✷
▼æ ❤➻♥❤ ✈❡❝tì tr➯♥ ♠➦t ♣❤➥♥❣
❊✉❝❧✐❞
❈❤÷ì♥❣ ♥➔② tr➻♥❤ ❜➔② sì ❧÷ñ❝ ✈➲ ❦❤→✐ ♥✐➺♠ ✈➔ ❜✐➸✉ ❞✐➵♥ ✤✐➸♠ ✈➔ ✈❡❝tì
t❤❡♦ tå❛ ✤ë ❝õ❛ ❝❤ó♥❣ tr➯♥ ♠➦t ♣❤➥♥❣ tå❛ ✤ë✳ ❈→❝ ❦✐➳♥ t❤ù❝ ♥➔② ♣❤ö❝
✈ö ❝❤♦ ✈✐➺❝ ①➙② ❞ü♥❣ ♣❤÷ì♥❣ tr➻♥❤ ✤÷í♥❣ tr♦♥❣ ♠➦t ♣❤➥♥❣ ❊✉❝❧✐❞ ð
❝❤÷ì♥❣ s❛✉✳ ❈→❝ ❦✐➳♥ t❤ù❝ ❝õ❛ ❝❤÷ì♥❣ ✤÷ñ❝ ✈✐➳t ❞ü❛ tr➯♥ ❝→❝ t➔✐ ❧✐➺✉
❬✷❪✱ ❬✹❪✳

✷✳✶ ❍➺ trö❝ tå❛ ✤ë ✣➲ ❝→❝ ✈✉æ♥❣ ❣â❝
✣➸ ①→❝ ✤à♥❤ ✈à tr➼ ❝õ❛ ✤✐➸♠ ✈➔ ❝õ❛ ✈❡❝tì tr➯♥ ♠➦t ♣❤➥♥❣ t❛ s➩ ①➙② ❞÷♥❣
❦❤→✐ ♥✐➺♠ ❤➺ trö❝ tå❛ ✤ë✳
❍➺ trö❝ tå❛ ✤ë ✣➲ ❝→❝ ✈✉æ♥❣ ❣â❝ tr♦♥❣ ♠➦t ♣❤➥♥❣ ❣ç♠ ❤❛✐ ✤÷í♥❣
t❤➥♥❣ ✈✉æ♥❣ ❣â❝
✈➔


x Ox ✈➔ y Oy

✱ tr➯♥ ✤â ❝❤å♥ ❤❛✐ ✈❡❝tì ✤ì♥ ✈à

−−→


e1 = OE1

−−→


e2 = OE 2 ✳
x ❖① ❣å✐ ❧➔ trö❝



e ✈➔ →
e ❣å✐ ❧➔ ❤❛✐

❍❛✐ ✤÷í♥❣ t❤➥♥❣ tr➯♥ ❣å✐ ❧➔ ❤❛✐ trö❝ tå❛ ✤ë✳ ❚rö❝
❤♦➔♥❤✱ trö❝

y Oy

❣å✐ ❧➔ trö❝ t✉♥❣✳ ❍❛✐ ✈❡❝tì ✤ì♥ ✈à

✈❡❝tì ❝ì sð✳

✶✽


1

2


õ tốt ồ



ồ ố tồ ở trử tồ ở t ố
ộ ồ ởt õ tồ ở ố õ tồ ở
trử tồ ở ồ t q tứ



e1





e2

t õ t

ữủ q ỗ ỗ ồ tr trữớ ủ ữủ


ồ ở ừ

r t tr õ õ ồ ởt trử tồ ở ổ õ

Oxy

q ữợ ồ tt t

tở t

Oxy

õ t

Oxy

sỷ ởt tũ ỵ

ỵ t õ




ON = x
e1 + y
e2
số ồ tồ ở ừ
t ở ừ

N




N (x; y).



N, x

ồ ở ồ


❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨

✷✳✸ ❚å❛ ✤ë ❝õ❛ ✈❡❝tì
❚r♦♥❣ ♠➦t ♣❤➥♥❣ tå❛ ✤ë

Oxy ✱

❝❤♦ ❝→❝ ✈❡❝tì tü ❞♦



α

t❤❡♦

✤à♥❤ ❧þ ✸ t❛

❝â✿






α = a1 →
e1 + a2 →
e2

a1 , a2 ❣å✐ ❧➔ tå❛ ✤ë ❝õ❛ ✈❡❝tì →
a tr♦♥❣




❤✐➺✉ ❧➔ a = (a1 ; a2 ) ❤♦➦❝ a (a1 ; a2 )✳

❈→❝ sè
❑➼

❈❤♦ ❤❛✐ ✤✐➸♠

X (x1 ; y1 )

✈➔

Y (x2 ; y2 )✳

♠➦t ♣❤➥♥❣


❚➻♠ tå❛ ✤ë ❝õ❛ ✈❡❝tì

❚❛ ❝â✿

−−→ −−→ −−→
XY = OY − OX
▼➦t ❦❤→❝✿

−−→


e1 + y1 →
e2
OX = x1 →
−−→


OY = x2 →
e1 + y2 →
e2
❑❤✐ ✤â✿

−−→ −−→ −−→


XY = OY − OX = (x2 − x1 ) →
e1 + (y2 − y1 ) →
e2
✷✵


Oxy ✳
−−→
XY ✳


❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨

❤❛②

−−→


XY = (x2 − x1 ) →
e1 + (y2 − y1 ) →
e2
−−→
XY ❝â tå❛ ✤ë ❧➔ (x2 − x1 ; y2 − y1 )
−−→
❧➔ XY = (x2 − x1 ; y2 − y1 )

❱➟② ✈❡❝tì
❑➼ ❤✐➺✉

❚å❛ ✤ë ❝õ❛ ✈❡❝tì tê♥❣ ✈➔ ✈❡❝tì ❤✐➺✉ ❝õ❛ ❤❛✐ ✈❡❝tì tü ❞♦





Oxy ❝❤♦ ❤❛✐ ✈❡❝tì →
a (a1 ; a2 ) ✈➔ ✈❡❝tì b (b1 ; b2 )✳ ❍➣②



− →

− →
✈❡❝tì tê♥❣ ❦➼ ❤✐➺✉ a + b ✈➔ ✈❡❝tì ❤✐➺✉ a − b ✳

❚r♦♥❣ ♠➦t ♣❤➥♥❣
t➻♠ tå❛ ✤ë ❝õ❛
❚❛ ❝â✿





a = a1 →
e1 + a2 →
e2




b = b1 →
e1 + b2 →
e2
❑❤✐ ✤â✿








a + b = (a1 + b1 ) →
e1 + (a2 + b2 ) →
e2
❤❛②





a + b = (a1 + b1 ; a2 + b2 )
✈➔







a − b = (a1 − b1 ) →
e1 + (a2 − b2 ) →
e2
❤❛②






a − b = (a1 − b1 ; a2 − b2 )
❱➟② tå❛ ✤ë ❝õ❛ ✈❡❝tì tê♥❣ ✭ ❤✐➺✉✮ ❜➡♥❣ tê♥❣ ✭❤✐➺✉✮ ❝→❝ tå❛ ✤ë t÷ì♥❣
ù♥❣ ❝õ❛ ❝→❝ ✈❡❝tì t❤➔♥❤ ♣❤➛♥✳

❚å❛ ✤ë ❝õ❛ ✈❡❝tì t➼❝❤ ❝õ❛ ♠ët ✈❡❝tì ✈î✐ ♠ët sè
❚r♦♥❣ ♠➦t ♣❤➥♥❣


k→
a


Oxy ✱ ❝❤♦ ✈❡❝tì →
a (a1 ; a2 )✳ ❍➣② t➻♠ tå❛ ✤ë ❝õ❛ ✈❡❝tì



✷✶


❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨

❚❛ ❝â✿






a = a1 →
e1 + a2 →
e2
❑❤✐ ✤â✿






k→
a = k a1 →
e1 + a2 →
e2 = ka1 →
e1 + ka2 →
e2

k→
a = (ka1 ; ka2 )

❱➟②✿

◆❤÷ ✈➟② t❤❡♦
❦❤æ♥❣




a (a1 ; a2 )

✤à♥❤ ❧þ ✷✱ tr♦♥❣ ♠➦t ♣❤➥♥❣



b (b1 ; b2 )

✈➔

Oxy

❤❛✐ ✈❡❝tì ❦❤→❝ ✈❡❝tì

❝ò♥❣ ♣❤÷ì♥❣ ❦❤✐ ✈➔ ❝❤➾ ❦❤✐✿

a2
a1
=
b1
b2
a1

❈❤ó þ✿

✈➔

a2

❝ô♥❣ ♥❤÷


b1

✈➔

b2

❦❤æ♥❣ ✤ç♥❣ t❤í✐ ❜➡♥❣

0✳

✷✳✹ ❇✐➸✉ t❤ù❝ ❝õ❛ t➼❝❤ ✈æ ❤÷î♥❣ ❝õ❛ ❤❛✐ ✈❡❝tì t❤❡♦
tå❛ ✤ë ❝õ❛ ❝❤ó♥❣
❚r♦♥❣ ♠➦t ♣❤➥♥❣ tå❛ ✤ë
t➻♠ ❜✐➸✉ t❤ù❝ ❝õ❛





a.b

Oxy





a (a1 ; a2 ), b (b1 ; b2 )✳





a, b✳

❝❤♦ ❤❛✐ ✈❡❝tì

t❤❡♦ tå❛ ✤ë ❝õ❛

❍➣②

❚❛ ❝â ✿





a = a1 →
e1 + a2 →
e2




b = b1 →
e1 + b2 →
e2
❱➟②








a . b = a1 →
e1 + a2 →
e2



e2
b1 →
e1 + b2 →

❚❛ ❝â ❝❤ó þ ✿


→ −



e2 1 = e2 2 = 1 ✈➻ →
e1 , →
e2 ❧➔ ♥❤ú♥❣ ✈❡❝tì ✤ì♥ ✈à ✭ ❤➺ q✉↔ ✹✮


− →



− →


− →
❜✳ e . e = 0 ✈➻ e ⊥ e ✭❤➺ q✉↔ ✺✮ ❉♦ ✤â a . b = a b + a b

❛✳

1

2

1

2

1 1

2 2

◆❤÷ ✈➟② t➼❝❤ ✈æ ❤÷î♥❣ ❝õ❛ ❤❛✐ ✈❡❝tì ❜➡♥❣ tê♥❣ ❝õ❛ ❝→❝ t➼❝❤ ❝õ❛ ❝→❝

✷✷


❑❤â❛ ❧✉➟♥ tèt ♥❣❤✐➺♣ ✣↕✐ ❤å❝

◆●❯❨➍◆ ❚❍➚ ❍⑨

tå❛ ✤ë t÷ì♥❣ ù♥❣ ❝õ❛ ❤❛✐ ✈❡❝tì ➜②✳






a ⊥ b ⇔ a1 a2 + b1 b2 = 0✳

−2

− →

2
2
❖①②✿ | a | = a . a = a1 + a2 ✳ ❉♦

❍➺ q✉↔ ✻✳ ❚r♦♥❣ ♠➦t ♣❤➥♥❣ ❖①②✿
❍➺ q✉↔ ✼✳ ❚r♦♥❣ ♠➦t ♣❤➥♥❣




a = a2 1 + a2 2 ✳

✤â✿

✷✳✺ ❱➼ ❞ö
❱➼ ❞ö ✷✳✺✳✶✳ ❚r♦♥❣ ♠➦t ♣❤➥♥❣ tå❛ ✤ë

Y (x2 ; y2 )✳


Oxy ✱

❚➻♠ ❦❤♦↔♥❣ ❝→❝❤ ❣✐ú❛ ❤❛✐ ✤✐➸♠

❝❤♦ ❤❛✐ ✤✐➸♠

X (x1 ; y1 )

✈➔

X, Y ❄

●✐↔✐✿

−−→
XY = (x2 − x1 ; y2 − y1 )
−−→2
−−→ 2 −−→
−−→
❚❤❡♦ ❤➺ q✉↔ ✸ t❤➻ XY
= XY = XY 2 tù❝ ❧➔ XY =
−−→
❚r♦♥❣ ✤â XY ❧➔ ❦❤♦↔♥❣ ❝→❝❤ ❣✐ú❛ ❤❛✐ ✤✐➸♠ X, Y ✳
❚❛ t❤➜②

❱➟②

XY =

−−→2

XY

(x2 − x1 )2 + (y2 − y1 )2

❱➼ ❞ö ✷✳✺✳✷✳ ❚r♦♥❣ ♠➦t ♣❤➥♥❣ Oxy ❝❤♦ ✤♦↕♥ t❤➥♥❣ AB ✈î✐ A(x1 ; y1 ), B(x2 ; y2 )✳
❚➻♠ ✤✐➸♠ ▼ s❛♦ ❝❤♦

−−→
−−→
M A = k M B (∗ ), k

✭❑❤✐ ✤â ✤✐➸♠ ▼ ❝❤✐❛ ✤♦↕♥ t❤➥♥❣

AB

❧➔ ♠ët sè ❝❤♦ tr÷î❝ ❦❤→❝ ✶✳

t❤❡♦ t➾ sè

k = 1✮

●✐↔✐✿
●å✐ tå❛ ✤ë ❝➛♥ t➻♠ ❝õ❛ ✤✐➸♠ ▼ ❧➔ ① ✈➔ ②✳

−−→
−−→
M A = (x1 − x; y1 − y)✱M B = (x2 − x; y2 − y)
−−→
−−→
❣✐↔ t❤✐➳t M A = k M B ✱ t❛ ❝â✿



 x − x = k (x − x)

❚❛ ❝â✿
❚❤❡♦

1

2


 y1 − y = k (y2 − y)

✷✸


×