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+j6pY3?XR5PE"N)j
          a-c=101
0s:f\.m#t7N"m           求bOs(i&j9J4jf2G#b

[)~u} FH           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)n4B ZFH
ab+bc-ac=0
)uV;Z2a J},ZdR N b(101-c)+bc-c(101-c)=0[*w1TU7~B UBP
101c-bc+bc-101c+(c*c)=0
5EH1F;azLn.W)R*? c*c=02s;E N'J-h,^-r2A p o
c=0
#IwW"Q}'gV8ZG}
g2yy;qZh8| a=101-0
lB ft4N&N2k a=101
CM{$RG*_ ffn.r 5Vi@8|#x{n6i
ab+bc-ac=0
c\d*BWk a=101
1BX PjH9C[9q c=0
$O:w^9YWK 101b + 0*b - 101*0=0
:u#a?mu0k N+u 101b=0
%w qO2T,b4i G 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:
a"a!\ G"d a=101-c;R{ F"rU*bI+y)\
ab+bc-ac=0[o @-~^ o LQ
b(101-c)+bc-c(101-c)=0
Q Km'B1},R#I 101c-bc+bc-101c+(c*c)=0
vyvD'U ?q5L!X c*c=0
Z6l~B LoLuz c=0
$^"K,zS V` $O7_,}_(A
a=101-0
LD;Y3ux b k a=101
*u3h IJhi;L^
\6Mun#b ab+bc-ac=0H0Bf}({s
a=101
} ?6n{ Y&d3e${$fmv c=0
%e2Z;vMlN&W ]C2g 101b + 0*b - 101*0=0
\0~ C kh3F8dS0V1S3[ 101b=0+r'S%ZWv9uP6W|
b=0 [/quote]
B+yB2y,Y`o
+jN-[NT8R^ m 對不起f2b;^*H8^ z2]
請容許我指出錯誤
%~;s i nlo7k8Oaj
!H4eX&jp5N-y 在一開頭 K'z+K @y*n0TagH

T2rV/`X:M/V-W [color=Red]a=101-c[/color](原本是a-c=101,移項應該是a=101+c)4rF_/E(up3}
ab+bc-ac=0Ol*|6m&TP+bO
[color=Red]b[/color]([color=Red]101[/color]-c)+bc-c(101-c)=0
:~)mbbC r@;^ [color=Red]101c[/color]-bc+bc-101c+(c*c)=05Z#`b#L_|/r
c*c=0
a0O\'M$aG2o c=0DQfH rj u
"^\&a.E6Zu!|~(i
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:zI.oS^'x,[ J {p
@4O A[%H`q

$[N/b'A4lx&gA 對不起}s8Gl.D)[)^
請容許我指出錯誤2@Z Zat%t

,wgNizz 在... [/quote]
M)@)tm3}DKYK 係bo
D$HG? [.j&PM 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:t{ ] C EPJ7R
a=101, b&c =0 :D [/quote]
Gdl/i1?.LF Nn ab+bc-ac=0%[JE4D%M9r~
          a-c=101
@d.c!G0Qo1ghw           求b pp\A&i Hkfzi6O
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:
!PuEc~ %X ^8{4B)N X
m5F H/fAV n
對不起
2[-g8r9nT7Hr+s 請容許我指出錯誤
c$wS,Um(c wY-Y9b 0oH2iz5o[
在... [/quote]E JXY6Bt

{V8s@xd-V2IL E 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:
}*cT9X~R3OJ`u
/]%]5b/p]6N `c8a6\)C
9Ht-E1i$\#cE 咁你又吾去計;);):P:P [/quote]
qdG[iR do
-K+a1}x*s6z;b.U playplay你串我?:mad::noway::fight::angry:(表情符號好好玩的說:D)
.X+~7`2I+L6{]$P8k *dd{6bHy"b
咁你呢~你又唔去計?:dev::dev:
1?}9ZJ2H0ltS { 5j'x(JUc-P2Rg i;|3[$\
等了這麼久也沒人貼答案出來
6Q3r,~!q]n7jL$y-X ]V~A!t
那麼讓小生物來獻醜了:redface::redface::redface:
/Bd/n@zU
S ~&s6s0@ t&K 手寫關係,所以上傳圖片先了(懶得去打)
E @1E(y"m8D?%sd,vM 8|%vj?Fo!Zo8b x
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...)2J,q!_S/f Z
C{6Q)Bw1X;R
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)`P:i)@cf9j+]}
&bX4M1@ _e([
用的不是甚麼古怪的方法,應該好易睇得明
4nz l4GTL
*B*w6G'cx\4U%\2E 這算一種對付三個未知數,但只有兩式的求整數解方法
e;Yx;Hn{
i)Gq/eb3u%F 有不明的話可以提出
Q z`4cM&i9z
rn$y.?i/NS)lf,x 不過我要訓醒頭覺先回覆到,好累的說(脫力中...)z]#o#y,EE v!xcr

T$q&JI/zJK's K [[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:
s!cc5p/uZ.R%ie*g
-c.fc8V [
$k)g$k wR1Hh2b playplay你串我?:mad::noway::fig... [/quote]:?tb\ i O

F$p:K5g1B UIn 乜咁快手ㄚㄚㄚㄚ:D:D:D:D
%Qe&fB)j
/F yM/q3_m8g(k 個答案可以咁.....h-n$xF3{3]-K[
}g[.H(Nr
1.ab+bc-ac=0
l^*}_VL1r_ a-c=1013L.A:}!S;xz
b=ac/(a+c)=(101c+c^2)/(101+2c);l2Tw)NV+P
設c=101n Jb};vx-b
101n代入c;{%i0Hf?j?pU%Z
b`R vK"_
[101^2*n+(101n)^2]/(101+202n),eWH)|p8M?0E
=[(101^2)n(n+1)]/[(101)(2n+1)]
r2A*Y m @2pN =[101n(n+1)]/(2n+1)ED@#r'MMk\
hpq8Nm;KVf
因為a、b、c是正整數
bAlT.l/C2[uk _-l 所以n是正整數!n}nl\
所以[101n(n+1)]/(2n+1)是整數&Y*K0`Nk K&At{y|g
2n+1=101(剩下的2n+1=n或2n+1=n+1,n沒有整數解)'a2F1yL9m&B1c`5r
n=50B `uvU o v{
a=5151  <--a-c=101
9m,GOP%Ap6L*EH1m b=2550  <--[101n(n+1)]/(2n+1)+Q&y G Rt"Aj
c=5050  <--c=101n
GZY8z \?Xw 答案:b=2550

sakura310 發表於 2008-1-18 12:27 AM

Filename: DSC01158.JPG
(b!m C'O`:s{cM Datetime | Downloaded by | Counts
|gc5y1]Q.ZD1cg 2008-01-18 00:25:24 | 阿感 | 2L v Ya)X'ms
2008-01-18 00:24:20 | playbr2 | 28Rz"eU F9b"sAx
2008-01-18 00:22:02 | 但丁 | 26|'eO#^3N,cs
A3cN)\2@#c+i4sy
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:
b0hP fkZq0O Filename: DSC01158.JPGr5FfBJv#U6f`
Datetime | Downloaded by | Counts
,r9E)v6c t:Y 2008-01-18 00:25:24 | 阿感 | 24f;O)Y(|8s
2008-01-18 00:24:20 | playbr2 | 2
4KW%c%L:\yGvw&@ 2008-01-18 00:22:02 | 但丁 | 2%c:t y%XeD4f

)f3dPW%b A8P 點解大家都down兩次? XD [/quote]
TGI}TD$JsuV#L
}ZlX I Q.B&D:k 我第一次開睇左2秒就close 左:P:P'uN!~bDZ6w
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:#n_"`hCk~E
Filename: DSC01158.JPGa.Lu"J0p9M,\
Datetime | Downloaded by | Counts
"p;rWi"[/T 2008-01-18 00:25:24 | 阿感 | 2
-| U0KP5i%X 2008-01-18 00:24:20 | playbr2 | 2!H&f_~$eA
2008-01-18 00:22:02 | 但丁 | 20V.r5]ftl(L*]WN
w!J A:Fp V9p{
點解大家都down兩次? XD [/quote]
&YEe,Q p N!w zPV,}#~/c
快d捉我錯處:D:D:D
Uu{&Z$D X[x 話吾定我都打錯 + - 符號
ZWhP;d;aN7r6w3q 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
uG3Vr\$['u/Oo 不過,c=101n哥度(解除n係正整數的限制,只是整數)
HzsV2pat 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~)F4P6w^)Ym+nG
知道{101,0,0}和{5151,2550,5050}係答案的話,當然沒問題N*S\,W*]
但原先是不知答案,所以唔知有無失根
,h\HB@lK4S
)U |iF"EYw 有時見到題目都感到有點不爽
}nh1uB8fQ 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.D-c @;hPAN*BP
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....]2G{$~u3d8K-n(q
I|?^1Uul K[p
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:
3n-x p*A km#[ 冇答案ga....
Q%?`k"w+] rc
4h k-o A$K 2條equation solve 唔到3個unknown ga.... [/quote]xp'R`.d.~1`d^ n
1{ P3[5W"?E
agree
"K&l#dPc9J
-`hzVX8j 2 equations 2 unknows
i.SPxs}3x7u@7A ` Z%F6_/~F8|fDg!Z
if 3 unknows there should be 3 equations
(NFM9x/B1rzH
'yk}$w K5yVP5w+` make it simple 2d\:P nQVT
$EVDU:q
say JJn4h [g XJ'`
o7X6ZC&C\'@7q sJ\:C
a + b +c = 3)a&@c5q5C E Lc6vX

6vT A,E$}y)j Y6n? a+b = 2
%o&OB*v(asyS
r#Y)mq(He$f then c is 1 7C p W"i5X;oV
/^ B.bG%SEW
a = 2 - b
0f&K3W{C N{3[eb:\/R
so 0 = 0
"i8?&v5dG^a0H1t 0t@Ch0`$T^5v
: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:
9CAro4VPC$] 冇答案ga....
(X'N*S In
2lu j\b 2條equation solve 唔到3個unknown ga.... [/quote]$Sjf }i#u P,s%Uh+W

t#fn|ce.Gn P 此言差矣~DL!M:[,u
5c1oZWrG-\7Z|'qD
2條equation solve 唔到3個unknown ga
1UM+pw,itV^ 還欠一個條件,就是3條equation都是linear independent(線性無關)的J L^Y8gU~
0y"?1t ]*b1}
簡單點說,多元一次方程就是線性方程的一個例子:Gn(yBm~O
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
H+F[U4}g &U?e0y~+J
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~)*q$P x'P/o3r.j
例如 x^2-2(x+8y)+17+4y^2+z^0.5=0 就只有唯一整數解
,I sa`;Tg(TD#NG 有興趣就解解看:sleep:J1_g D8Nd1V+ic~
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:
o3g^+~5er:IO5Yy 8\X {LKI
%P&FsHe
不懂的話就問playplay,佢會知答案[/quote]VC)x]2rx'n

#N4T:?"R:{0iD*x6uR :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:3[O9WM8K4d|
捉錯處就唔敢當
$|X?(aslR*M{ \;f"c 不過,c=101n哥度(解... [/quote]C'@K2B%`*{
2zG,B4}#Vr\:C
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L{8`#}rB)M"g,xgEo
反而適當地調節一下 , 咁會理性好多
vsKE/X_+? 就好似隻game 由12粒珠 加到13粒珠咁o(gpA/\ N ?W;S
當''堂''好玩哂:P:P:PS@9R?XsUU
,T@AU*x)}5Z @6\5m
p.s. 求''堂''字正寫:agree::giveup:

QuiGonJinn 發表於 2008-1-19 03:49 AM

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