娛樂滿紛 26FUN's Archiver

SKII999 發表於 2008-1-17 07:26 PM

想問大家一條數,,

ab+bc-ac=0!T4N1L bT!l
          a-c=101
`9U\;M.X*yb(u1C           求bl$zB1X k
8k|b4c%{ eCf
          要STEPS,,,THX

托迪仔T 發表於 2008-1-17 07:42 PM

a=101, b&c =0 :D

SKII999 發表於 2008-1-17 07:52 PM

我都知,,但唔知點得出個ans.,,anyway,,THX

ch.chak 發表於 2008-1-17 09:38 PM

a=101-c:U dq La9W6h
ab+bc-ac=0
H&_7z oM|8e-G/k[} b(101-c)+bc-c(101-c)=0C4]p.Z&qt6|
101c-bc+bc-101c+(c*c)=0
0GPKo$@yP;r6dL c*c=0q1e3Uk9x @u
c=0fG3N+j}%q u

U*FX4n[F a=101-0
9g(gKlRv5WjAX a=101
-`3KF l+yv$h2f '`P6F_mq
ab+bc-ac=0 M1v|| m-|9S
a=101
+~#z@K|e c=0
V{}'fd(| C 101b + 0*b - 101*0=0!h!Ynm2D9cL3^
101b=0W-BP&?/d;z
b=0

sakura310 發表於 2008-1-17 09:58 PM

[quote]Originally posted by [i]ch.chak[/i] at 2008-1-17 09:38 PM:
!@-]%Ix2Lv0]m a=101-c
a)E[)?:{-]s2W ab+bc-ac=0,I/k(rsO(HM
b(101-c)+bc-c(101-c)=0$e }6M2sNJ4N d
101c-bc+bc-101c+(c*c)=02e5c]8ge.BHu Q
c*c=0'L8|:xFf)L4T{
c=0&qN#n/F9I$c
f4@,K.k-M+}v6v
a=101-0*Z#Y2?a*T)N"I
a=101 j0N/? rT2GJ6Xu

uE(U|9E8x2d ab+bc-ac=0
/Q WhhJL/Xq@9S a=101
P7K?F7k5? c=09f8V$}3f%oh.[9`0}V+dZ.q
101b + 0*b - 101*0=0
8z*Y!mRe1T$t 101b=0
/N'Q+p5Bx?/Dg&n b=0 [/quote]
~$gvM O6`
s*DsTov4T 對不起
iy6Np\ 請容許我指出錯誤
,]4wS'X G kX BW_g
在一開頭
X BK @BC `| *]7yfm4Z%Z|/J
[color=Red]a=101-c[/color](原本是a-c=101,移項應該是a=101+c)
8M2N }6ZB,YI#J ab+bc-ac=0|4k c]J~;R
[color=Red]b[/color]([color=Red]101[/color]-c)+bc-c(101-c)=0"Q_X uu `,u
[color=Red]101c[/color]-bc+bc-101c+(c*c)=0 Qey Hn/a!o @-@)a4f+Mm
c*c=0
%{%w*B0D }7Dk c=0.x^:r @;K5d

A n!fjaD E 基於以上紅字的地方,其餘的地方我認為沒必要看了

ch.chak 發表於 2008-1-17 10:53 PM

[quote]Originally posted by [i]sakura310[/i] at 2008-1-17 09:58 PM:[l;IBV R
7j3WET M]n3B$^

A;rcQ9k k 對不起8^Zfc1KP
請容許我指出錯誤
xN'd-sOD7fq4o C$`
~[8s^ b^GVhe] 在... [/quote]4{2MA*O"KR3e
係bo7dKX$etE
冇留意錯左tim

呀俊 發表於 2008-1-17 11:00 PM

[quote]Originally posted by [i]托迪仔T[/i] at 2008-1-17 07:42 PM:2IZ/O/d SO
a=101, b&c =0 :D [/quote]
!n"u ["hE|BD k ab+bc-ac=0
4t9oc!H-edD U)_           a-c=101
V.l#}r9}?4C ]           求b
iFM9s5_-| DA 咁玩法...如果c係-101...a同b=0 都得架wo:D

playbr2 發表於 2008-1-17 11:58 PM

[quote]Originally posted by [i]sakura310[/i] at  09:58 PM:
LbDZ-Gt
2kNo!p+OD*Y%\
0u*~:] L%H)g9t K`#B 對不起$hC it5J
請容許我指出錯誤6u"F;^~3wT'vN

:l%W5OA3g 在... [/quote]
?PFk4C%v wVG&e B [n h'y)\ [0o Z+t8G+t$l,u
咁你又吾去計;);):P:P

sakura310 發表於 2008-1-18 12:08 AM

[quote]Originally posted by [i]playbr2[/i] at 2008-1-17 11:58 PM:
yAg:mL1y5P fj{7El!sh'Gv

#KC2B"O:E@9q z 咁你又吾去計;);):P:P [/quote]
-vr[-Rc
9I,b_(p"an;O iA playplay你串我?:mad::noway::fight::angry:(表情符號好好玩的說:D)
c s?VP
)rf'Xe(G-H 咁你呢~你又唔去計?:dev::dev:
t9tCAY}:Eh ZE
A)|'t#_!KuS+x)J5X 等了這麼久也沒人貼答案出來fP}J6DQ n9Y

F N ~O3cS/D 那麼讓小生物來獻醜了:redface::redface::redface:
7S+KsJ WD#@ z %Z_&A`@&rnct
手寫關係,所以上傳圖片先了(懶得去打)
!N2K ^U5z8uA1oNA 5M6~1fB"YL0q4@sCY9f
由於題目沒有說到a,b和c是甚麼數,我暫且假設係整數黎做(光是實數的話...太沒意思了...)
&|#aBK;k"^ L4Q.P\ L Ad G/L$W;z Qyc'b
如果是實數的話,那麼請看到左邊2/3就可以了,中間和右邊是整數的解集(次序:左>中>右)
\K {}1n dM_};a:r-h-j
用的不是甚麼古怪的方法,應該好易睇得明
Ex|(@1P1sAF x6e;Y xHV md9j:fU\7dl
這算一種對付三個未知數,但只有兩式的求整數解方法"]@/I0\ [5jB%H/?

EvQS-nK 有不明的話可以提出5] oA{y i#W|L4w

I3Y%B jS;t*Z"j v,LJ 不過我要訓醒頭覺先回覆到,好累的說(脫力中...)
/@za-\ B;M~ m#O^ WU+F
[[i] Last edited by sakura310 on 2008-1-18 at 12:12 AM [/i]]

playbr2 發表於 2008-1-18 12:21 AM

[quote]Originally posted by [i]sakura310[/i] at  12:08 AM:#J ]wm Pk
$o0kCSSN;t/NMc
Or5{^UV
playplay你串我?:mad::noway::fig... [/quote]
fxl?(vUd(G
5PR L\/ss 乜咁快手ㄚㄚㄚㄚ:D:D:D:D
%c%|eYp Vxgn-WI+{
個答案可以咁.....L zhm6l'j)`
;p9Cp-i3X o]!Q,_v
1.ab+bc-ac=0$V0}5c|g;a`E/@
a-c=1012v*W6HqG {f
b=ac/(a+c)=(101c+c^2)/(101+2c)%nV-x&? G)Iev8C:k
設c=101n
fnRG9rZ 101n代入c
qUa5G;^+O ?%q&AL
qY4nD,t,F+Y/e [101^2*n+(101n)^2]/(101+202n)
[1G%r$| },y =[(101^2)n(n+1)]/[(101)(2n+1)]5a.NJ2g~IGF|jp
=[101n(n+1)]/(2n+1)q e`MB:v~Y

Wq6z2C9r%@[pk 因為a、b、c是正整數
1ND cl!s 所以n是正整數(o [r-Z-K
所以[101n(n+1)]/(2n+1)是整數
d!v UP7V ] 2n+1=101(剩下的2n+1=n或2n+1=n+1,n沒有整數解)-sa8o`7}O!| O{
n=50
evNi2L(pmAgn a=5151  <--a-c=101r9h%sa F
b=2550  <--[101n(n+1)]/(2n+1)oN-dif!y ?x
c=5050  <--c=101n
Qf4l7l,w7i0Y 答案:b=2550

sakura310 發表於 2008-1-18 12:27 AM

Filename: DSC01158.JPG`2E?,k[
Datetime | Downloaded by | Counts
2D oCDx| 2008-01-18 00:25:24 | 阿感 | 2
%WR@9n8Xn@!] 2008-01-18 00:24:20 | playbr2 | 2
!a[|5}7~d8B 2008-01-18 00:22:02 | 但丁 | 2'{mix1dn e8r'SJ
)C.~)E/^M,t6n&G!BjF
點解大家都down兩次? XD

playbr2 發表於 2008-1-18 12:30 AM

[quote]Originally posted by [i]sakura310[/i] at  12:27 AM:
E7t;].mN0c Filename: DSC01158.JPG;l1S+F3s(f
Datetime | Downloaded by | Counts
G e1l8dt0[ 2008-01-18 00:25:24 | 阿感 | 2
?`*w`Z LUN&aa:}V 2008-01-18 00:24:20 | playbr2 | 2
6j5ZW1e l6y 2008-01-18 00:22:02 | 但丁 | 22v/xv(])x^

eD*kz4w*Qr-f]0q 點解大家都down兩次? XD [/quote]
lg7GqesJ gN? ^4?cR}:R
我第一次開睇左2秒就close 左:P:P
yhk)R Jbs x 之後DL (就变成第二次)

playbr2 發表於 2008-1-18 12:34 AM

[quote]Originally posted by [i]sakura310[/i] at  12:27 AM:${j hU'A Q
Filename: DSC01158.JPG
f0r;F&M0M1r3JZ:]'O Datetime | Downloaded by | Counts+P"k6@V;@7K&eb$SUM
2008-01-18 00:25:24 | 阿感 | 2
(AE:h3X?#{T 2008-01-18 00:24:20 | playbr2 | 2
?$Wo(AR0D7GK 2008-01-18 00:22:02 | 但丁 | 24Gn e-{9LBM4Nh:a

Wf0Q B;hG4wv 點解大家都down兩次? XD [/quote] sl,^X|x7@

U8d OMMew 快d捉我錯處:D:D:D
;Z \_J7J 話吾定我都打錯 + - 符號IdCPE Y]G D&`
係電腦打答案...的確幾煩...又哂時間...:giveup:

sakura310 發表於 2008-1-18 06:47 AM

捉錯處就唔敢當
XSiZY sn| 不過,c=101n哥度(解除n係正整數的限制,只是整數)!c7OPKA o O*F
就一下子限制左c一定要係101的倍數(好像看懸疑片,突然劇情說出一些事前沒提及過的線索,不爽~)
,J)_&cJ/g%| 知道{101,0,0}和{5151,2550,5050}係答案的話,當然沒問題9X,p8HJ,|^N6]o
但原先是不知答案,所以唔知有無失根
H*^6\$nSx1t
9yRm7Aa%tF-G 有時見到題目都感到有點不爽1q%G+k7i(M3uG$z{
題目所求的答案是整數,正整數,有理數,實數等等應該說清楚Y.m%S-K@,{4b(OL
有些題目,整數解和正整數解分別好大的說,要找出整數解集有時可不是件易事= =

cutec 發表於 2008-1-18 08:26 AM

冇答案ga....
6d6]+{(R2YnQ&` lSl0i-lH@z
2條equation solve 唔到3個unknown ga....

Azuma 發表於 2008-1-18 08:56 AM

[quote]Originally posted by [i]cutec[/i] at 2008-1-18 08:26 AM: T:nwd8SR-eJuc
冇答案ga....
"g.P/RYpg9Vj
z$Eri cRCpm 2條equation solve 唔到3個unknown ga.... [/quote]n6q-a Ln\

q s2V}9t:[&~1u agree q0s lT Csl
&Ag1\l8JN/X
2 equations 2 unknows
(B4yr_&N8TC [,JU)cE
_ {0k*[;U(g if 3 unknows there should be 3 equations .yzHLL$Fl'Im!\3|

S"VxG,[k make it simple
,C"cj2iGY
;n2tU$n%Y,[Q6HE['jd say (m`o$C ~
Vg2`m)A3[T
a + b +c = 3
Qh v$K+w!KhyNK B1JD'a/zB9lUKM
a+b = 2
5`j*Kc,Q.E.aH
w4j H0j1vt0["T,u then c is 1
|o}j;|gU
\O~b&j Ot`yN] a = 2 - b })`N5z M `3r'b KD1I
N%X;h'Lj_ h,_
so 0 = 0 |3Z eGH,e?

+X?.yN s ~_r :giveup:

sakura310 發表於 2008-1-18 10:22 AM

[quote]Originally posted by [i]cutec[/i] at 2008-1-18 08:26 AM:)L.`n#SjD/_g
冇答案ga....
-E_E[/lZz5NG8t :w1b8H$?i7x@ cuh
2條equation solve 唔到3個unknown ga.... [/quote]i.P6B:s4R-x

'pi-FS c*t 此言差矣~
a0c8z/K l(|YM*h C&q {%@ X R4g,{
2條equation solve 唔到3個unknown ga!?7ckP$Le h
還欠一個條件,就是3條equation都是linear independent(線性無關)的CFk,ZE j
*M/r ` z$z"C | O5E
簡單點說,多元一次方程就是線性方程的一個例子
k#t%juU&?`Ke)QqB+M 在這情況下,當然是想求n個未知數,至少要用n條線性無關的方程
]_)mym6h TZ E%qj#j/cT[5b
如果不是線性的話,有機會1條方程解3個未知數的(這不是每次都可以的啦~)mj*A"DM$X
例如 x^2-2(x+8y)+17+4y^2+z^0.5=0 就只有唯一整數解
F#f7F/b&OgN 有興趣就解解看:sleep:!]$W5_9BR2s d
不懂的話就問playplay,佢會知答案:dev:

playbr2 發表於 2008-1-18 02:47 PM

[quote]Originally posted by [i]sakura310[/i] at  10:22 AM:MK8i)v)eX
^#d!kx(p[
pI5ptmyX
不懂的話就問playplay,佢會知答案[/quote]*X'G6v[G%N

N9[G5s6q~ :cry::giveup::giveup::giveup::giveup:

playbr2 發表於 2008-1-18 02:57 PM

[quote]Originally posted by [i]sakura310[/i] at  06:47 AM:-{$v$k.Y"r3U8ua
捉錯處就唔敢當
Bv3m] Yg 不過,c=101n哥度(解... [/quote]
v;og#T{6_1M
(v"d![7TVt\ n,{ 都係睇餸食飯姐 , 無理由因為題目冇同你假設就下下大包圍架?S7tgc W:eN(wP
反而適當地調節一下 , 咁會理性好多A A&H$S6y
就好似隻game 由12粒珠 加到13粒珠咁i*y/Q]F,m,C$A,Qvs
當''堂''好玩哂:P:P:P.iwFN;~u T;mo
5X%}]u0gFh gZ2n
p.s. 求''堂''字正寫:agree::giveup:

QuiGonJinn 發表於 2008-1-19 03:49 AM

**** 作者被禁止或刪除 內容自動屏蔽 ****

頁: [1] 2

Powered by Discuz! Archiver 7.0.0  © 2001-2009 Comsenz Inc.