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"dinlsa`udirpayslks.ln" 9
I klrk bj ls i bhkus hf i phlnt ln i pbinj wahsj olstinkj frhd i flxjo phlnt (kibbjo kjntrj) ls ibwiys
khnstint (kibbjo riolus).
Jquitlhn hf i klrkbj ln virlhus fhrds(i) _aj klrkbj wlta kjntrj is hrlcln & riolus r ais taj jquitlhn0 x7 + y7 4 r7.
(g) _aj klrkbj wlta kjntrj (a, `) & riolus r ais taj jquitlhn0 (x a)7 + (y` )7 4 r7.
(k) _aj cjnjrib jquitlhn hf i klrkbj ls
x7 + y7 + 7cx + 7fy + k 4 =
wlta kjntrj is (c,f) & riolus 4 kfc 77 .
_als kin gj hgtilnjo frhd taj jquitlhn
(x a)7 + (y `)7 4 r7
x7 + y7 7ax 7`y + a7 + `7 r7 4 =_i`j a 4 c, ` 4 f ino a7 + `7 r7 4 k
Khnoltlhn th ojflnj klrkbj 5-
c + f k > = rjib klrkbj.
c + f k 4 = phlnt klrkbj.c + f k 2 = ldiclniry klrkbj, wlta rjib kjntrj, tait ls ( c, f)
Nhtj 5 _ait jvjry sjkhno ojcrjj jquitlhn ln x & y, ln walka khjfflkljnt hf x7 ls jquib th khjfflkljnt hf y7 & taj
khjfflkljnt hf xy ls zjrh, ibwiys rjprjsjnts i klrkbj.
(o) _aj jquitlhn hf klrkbj wlta (x9, y
9) & (x
7, y
7) is jxtrjdjtljs hf lts olidjtjr ls5
(x x9) (x x
7) + (y y
9) (y y
7) 4 =.
Klrkbj
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"dinlsa`udirpayslks.ln" 7
_als ls hgtilnjo gy taj fikt tait incbj ln i sjdlklrkbj ls i rlcat incbj.
([bhpj hf ]I) ([bhpj hf ]G) 4 9
9
9
xx
yy
.7
7
xx
yy
4 9
(x x9) (x x
7) + (y y
9) (y y
7) 4 =
Nhtj tait tals wlbb gj taj klrkbj hf bjist riolus pisslnc tarhuca (x9, y
9) & (x
7, y
7).
Jxidpbj # 9 5 Flno taj jquitlhn hf taj klrkbj wahsj kjntrj ls (9, 7) ino riolus ls ?.
[hbutlhn 5 _aj jquitlhn hf taj klrkbj ls (x 9)7 + (y (7))7 4 ?7
(x 9)7 + (y + 7)7 4 96 x7 + y7 7x + ?y 99 4 = Ins.
Jxidpbj # 7 5 Flno taj jquitlhn hf taj klrkbj walka pissjs tarhuca taj phlnt hf lntjrsjktlhn hf taj blnjs ;x
7y 9 4 = ino ?x + y 73 4 = ino wahsj kjntrj ls (7, ;).
[hbutlhn 5 Bjt ] gj taj phlnt hf lntjrsjktlhn hf taj blnjs IG ino BD wahsj jquitlhns irj rjspjktlvjby
;x 7y 9 4 = ..........(l)
ino ?x + y 73 4 = ..........(ll)[hbvlnc (l) ino (ll), wj cjt x 4 :, y 4 3. [h, khhrolnitjs hf ] irj (:, 3). Bjt K(7, ;) gj taj
kjntrj hf taj klrkbj. [lnkj taj klrkbj pissjs tarhuca ], tajrjfhrj
K] 4 riolus 77 );3()7:(
riolus 4 9=< .Ajnkj taj jquitlhn hf taj rjqulrjo klrkbj ls
(x 7)7 + (y + ;)7 4 79= k klrkbj kuts taj x ixls it twh olstlnkt phlnts.
c7 4 k klrkbj thukajs taj xixls.
c7 2 k klrkbj bljs khdpbjtjby ighvj hr gjbhw taj xixls.
IG 4 7IO 4 7 77 KOr 4 7 77 fr 4 7 7777 fkfc 4 7 kc7
Jxidpbj # : Flno taj jquitlhn th taj klrkbj thukalnc taj njcitlvj y-ixls it i olstinkj ; frhd taj hrlcln ino
lntjrkjptlnc i bjncta 1 hn taj x-ixls.
[hbutlhn 5 Bjt taj jquitlhn hf taj klrkbj gj x7 + y7 + 7cx + 7fy + k 4 =. [lnkj lt thukajs y-ixls it (=, ;)
ino (=, ;) bljs hn taj klrkbj.
k 4 f7 ...(l) < 6f + k 4 = .......(ll)Frhd (l) ino (ll), wj cjt < 6f + f7 4 = (f ;)7 4 = f 4 ;.]uttlnc f 4 ; ln (l) wj hgtiln k 4
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"dinlsa`udirpayslks.ln" ?
Jxidpbj # 6 5 Flno taj piridjtrlk jquitlhns hf taj klrkbj x7 + y7 ?x 7y + 9 4 =
[hbutlhn 5 Sj aivj 5 x7 + y7 ?x 7y + 9 4 = (x7 ?x ) + (y7 7y) 4 9 (x 7)7 + (y 9)7 4 77
[h, taj piridjtrlk jquitlhns hf tals klrkbj irj
x 4 7 + 7 khs , y 4 9 + 7 sln.
Jxidpbj # 3 5 Flno taj jquitlhns hf taj fhbbhwlnc kurvjs ln kirtjslin fhrd. Ibsh, flno taj kjntrj ino riolus hf
taj klrkbj x 4 i + k khs, y 4 g + k sln
[hbutlhn 5 Sj aivj 5 x 4 i + k khs, y 4 g + k sln khs 4k
ix, sln 4
k
gy
7
k
ix
+
7
k
gy
4 khs7 + sln7 (x i)7 + (y g)7 4 k7
Kbjirby, lt ls i klrkbj wlta kjntrj it (i, g) ino riolus k.
[jbf priktlkj prhgbjds 5
(6) Flno taj piridjtrlk jquitlhns hf klrkbj x7 + y7 6x + ?y 97 4 =
(3) Flno taj kirtjslin jquitlhns hf taj kurvj x 4 7 + ; khs, y 4 ; + ; sln
Inswjrs 5 (6) x 4 ; + : khs, y 4 7 + : sln (3) (x + 7)7 + (y ;)7 4 =.
Nhtj 5 _aj crjitjst & taj bjist olstinkj hf i phlnt I (bljs hutsloj taj klrkbj) frhd i klrkbj wlta kjntrj K &
riolus r ls IK + r & IK r rjspjktlvjby.
Jxidpbj # 1 5 Olskuss taj phsltlhn hf taj phlnts (9, 7) ino (6, =) wlta rjspjkt th taj klrkbj
x7 + y7 ?x + 7y 99 4 =
[hbutlhn 5 Sj aivj x7 + y7 ?x + 7y 99 4 = hr [ 4 =, wajrj [ 4 x7 + y7 ?x + 7y 99.
Fhr taj phlnt (9, 7), wj aivj [94 97 + 77 ? 9 +7 7 99 2 =
Fhr taj phlnt (6, =), wj aivj [74 67 + =7 ? 6 +7 = 99 > =
Ajnkj, taj phlnt (9, 7) bljs lnsloj taj klrkbj ino taj phlnt (6, =) bljs hutsloj taj klrkbj.
[jbf priktlkj prhgbjd 5
(1) A hw i rj t a j ph ln ts ( = , 9 ) ( ;, 9 ) i n o (9 , ; ) s lt ui tj o w lt a r js pj k t th t aj k l rk b j
x7 + y7 7x ?y + ; 4 =8
Inswjr 5 (1) (=, 9) bljs hn taj klrkbj 0 (;, 9) bljs hutsloj taj klrkbj 0 (9, ;) bljs lnsloj taj klrkbj.
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"dinlsa`udirpayslks.ln" :
Blnj ino i klrkbjBjt B 4 = gj i blnj & [ 4 = gj i klrkbj. Lf r ls taj riolus hf taj klrkbj & p ls taj bjncta hf taj pjrpjnolkubir
frhd taj kjntrj hn taj blnj, tajn5
(l) p > r taj blnj ohjs nht djjt taj klrkbj l. j. pissjs hut sloj taj klrkbj.(ll) p 4 r taj blnj thukajs taj klrkbj. (Lt ls tincjnt th taj klrkbj)(lll) p 2 r taj blnj ls i sjkint hf taj klrkbj.(lv) p 4 = taj blnj ls i olidjtjr hf taj klrkbj.Ibsh, lf y 4 dx + k ls blnj ino x7 + y7 4 i7 ls klrkbj tajn
(l) k7 2 i7 (9 + d7) taj blnj ls i sjkint hf taj klrkbj.(ll) k7 4 i7 (9 + d7) taj blnj thukajs taj klrkbj. (Lt ls tincjnt th taj klrkbj)(lll) k7 > i7 (9 + d7) taj blnj ohjs nht djjt taj klrkbj l. j. pissjs hut sloj taj klrkbj.
_ajsj khnoltlhns kin ibsh gj hgtilnjo gy shbvlnc y 4 dx + k wlta x7 + y7 4 i7 ino di`lnc taj olskrldlnint
hf taj quioritlk crjitjr tain zjrh fhr sjkint, jquib th zjrh fhr tincjnt ino bjss taj zjrh fhr taj bist kisj.
Jxidpbj # < 5 Fhr wait vibuj hf k wlbb taj blnj y 4 7x + k gj i tincjnt th taj klrkbj x 7 + y7 4 : 8
[hbutlhn 5 Sj aivj 5 y 4 7x + k hr 7x y + k 4 = ......(l) ino x7 + y7 4 : ........(ll)
Lf taj blnj (l) thukajs taj klrkbj (ll), tajn
bjncta hf taj frhd taj kjntrj (=, =) 4 riolus hf klrkbj (ll)
77 )9(7
k==7
4 :
:
k4 :
:
k4 : k 4 :
Ajnkj, taj blnj (l) thukajs taj klrkbj (ll) fhr k 4 :
[jbf priktlkj prhgbjd 5
(
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"dinlsa`udirpayslks.ln" 6
Nhtj 5 Ln cjnjrib taj jquitlhn hf tincjnt th iny sjkhno ojcrjj kurvj it phlnt (x9,
y9) hn lt kin gj hgtilnjo gy
rjpbiklnc x7 gy x x9,
y7 gy yy9,
x gy7
xx 9, y gy
7
yy 9,
xy gy7
yxyx 99 ino k rjdilns is k.
]iridjtrlk fhrd hf tincjnt_aj jquitlhn hf i tincjnt th klrkbj x 7 + y7 4 i7 it (ikhs , i sln ) lsx khs + y sln 4 i.
NH_J 5 _aj phlnt hf lntjrsjktlhn hf taj tincjnts it taj phlnts ]() & Y() ls
7
7
7
7
khs
slni,
khs
khsi
Jxidpbj#9=5 Flno taj jquitlhn hf taj tincjnt th taj klrkbj x7 + y7 ;=x + 6y + 9=< 4 = it (?, 9).
[hbutlhn 5 Jquitlhn hf tincjnt ls
?x + (y) ;=
7
?x+ 6
7
)9(y+ 9=< 4 =
hr ?x y 9:x 6= + ;y ; + 9=< 4 = hr 99x + 7y + ?6 4 =
hr 99x 7y ?6 4 =
Ajnkj, taj rjqulrjo jquitlhn hf taj tincjnt ls 99x 7y ?6 4 =
Jxidpbj # 99 5 Flno taj jquitlhn hf tincjnts th taj klrkbj x 7 + y7 6x + ?y 97 4 = walka irj piribbjb th taj
blnj ?x + ;y + : 4 =
[hbutlhn 5 Clvjn klrkbj ls x7 + y7 6x + ?y 97 4 = ... ....(l)
ino clvjn blnj ls ?x + ;y + : 4 = .......(ll)
Kjntrj hf klrkbj (l) ls (;, 7) ino lts riolus ls :. Jquitlhn hf iny blnj
?x + ;y + 4 = piribbjb th taj blnj (ll) .......(lll)
Lf blnj (lll) ls tincjnt th klrkbj, (l) tajn
77 ;?
|`)7(;;.?|
4 : hr |6 + `| 4 7:
hr 6 + 4 7: ` 4 9
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"dinlsa`udirpayslks.ln" 3
Jxidpbj# 975 Flno taj jquitlhn hf taj nhrdib th taj klrkbj x 7 + y7 :x + 7y ?1 4 = it taj phlnt (:, 6).
[hbutlhn 5 [lnkj nhrdib ls blnj ehlnlnc kjntrj
9,
7
:ino (:, 6)
[bhpj 4:
9?
Ajnkj, taj jquitlhn hf taj nhrdib it (:, 6) lsy 6 4 (9?/:) (x :) 9?x :y ?= 4 =
[jbf priktlkj prhgbjd 5
(99) Flno taj jquitlhn hf taj nhrdib th taj klrkbj x7 + y7 7x ?y + ; 4 = it taj phlnt (7, ;).
Inswjr 5 (99) x y + 9 4 =
]ilr hf tincjnts frhd i phlnt_aj jquitlhn hf i pilr hf tincjnts oriwn frhd taj phlnt I (x
9,y
9) th taj klrkbj
x7 + y7 + 7cx + 7fy + k 4 = ls 5 [[9
4 _.
Sajrj [ x7 + y7 + 7cx + 7fy + k 0 [9 x
9 + y
9 + 7cx
9+ 7fy
9+ k
_ xx9
+ yy9
+ c(x + x9) + f(y + y
9) + k.
Jxidpbj # 9; Flno taj jquitlhn hf taj pilr hf tincjnts oriwn th taj klrkbj x7 + y7 7x + ?y 4 = frhd taj phlnt
(=, 9)
[hbutlhn 5 Clvjn klrkbj ls [ 4 x7 + y7 7x + ?y 4 = ... ....(l)
Bjt ] (=, 9)Fhr phlnt ], [
94 =7 + 97 7.= + ?.9 4 :
Kbjirby ] bljs hutsloj taj klrkbj
ino _ x . = + y . 9 (x + =) + 7 (y + 9)l.j. _ x +;y + 7.Nhw jquitlhn hf pilr hf tincjnts frhd ](=, 9) th klrkbj (9) ls [[
94 _7
hr : (x7 + y7 7x + ?y) 4 ( x + ;y + 7)7
hr :x7 + :y7 9=x + 7=y 4 x7 +
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"dinlsa`udirpayslks.ln" 1
[jbf priktlkj prhgbjds 5
(97) Flno taj ehlnt jquitlhn hf taj tincjnts tarhuca (3, 9) th taj klrkbj x7 + y7 4 7:.
Inswjr 5 (97) 97x7 97y7 + 3xy 93:x 7:y + 67: 4 =
Bjncta hf i tincjnt ino phwjr hf i phlnt_aj bjncta hf i tincjnt frhd in jxtjrnib phlnt (x
9,y
9) th taj klrkbj
[ x7 + y7 + 7cx + 7fy + k 4 = ls clvjn gy B 4 kyf7xc7yx 997
97
9 4 9[ .
I] 4 bjncta hf tincjnt
I]7 4 IO . IJ
[quirj hf bjncta hf taj tincjnt frhd taj phlnt I ls ibsh kibbjo taj phwjr hf phlnt w.r.t. i klrkbj.
]hwjr hf i phlnt w.r.t. i klrkbj rjdilns khnstint.
]hwjr hf i phlnt ] ls phsltlvj, njcitlvj hr zjrh ikkhrolnc is taj phlnt I ls hutsloj, lnsloj hr hn taj
klrkbj rjspjktlvjby.
Jxidpbj # 9? Flno taj bjncta hf taj tincjnt oriwn frhd taj phlnt (:, 9) th taj klrkbj x 7 + y7 + 6x ?y ; 4 =
[hbutlhn 5 Clvjn klrkbj ls x7 + y7 + 6x ?y ; 4 = .........(l)
Clvjn phlnt ls (:, 9). Bjt ] 4 (:, 9)
Nhw bjncta hf taj tincjnt frhd ](:, 9) th klrkbj (l) 4 ;9.?:.69: 77 4 3
[jbf priktlkj prhgbjds 5
(9;) Flno taj irji hf taj quiorlbitjrib fhrdjo gy i pilr hf tincjnts frhd taj phlnt (?, :) th taj klrkbj
x7 + y7 ?x 7y 99 4 = ino i pilr hf lts rioll.
(9?) Lf taj bjncta hf taj tincjnt frhd i phlnt (f, c) th taj klrkbj x7 + y7 4 ? gj fhur tldjs taj bjncta hf
taj tincjnt frhd lt th taj klrkbj x7 + y7 4 ?x, sahw tait 9:f7 + 9:c7 6?f + ? 4 =
Inswjr. (9;) 1 s q. unlts
Olrjkthr k lrkbj_aj bhkus hf taj phlnt hf lntjrsjktlhn hf twh pjrpjnolkubir tincjnts ls kibbjo taj olrjkthr klrkbj hf taj
clvjn klrkbj. _aj olrjkthr klrkbj hf i klrkbj ls taj khnkjntrlk klrkbj aivlnc riolus jquib th 7 tldjs taj
hrlclnib klrkbj.
]rhhf 5
IK 4 r khsjk ?: 4 7r
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"dinlsa`udirpayslks.ln"