主項變換 [ x ]
y=2x/x-2
y=x+2/2-x
y=3x+1/x-1
以上這3條數,都是我備課見到,,
但是我做極都在第3個步驟度失敗左(因為書後有答案)
所以我就po上黎睇下有冇人識.最好列埋步驟..
maths
2007-10-15 3:57 am
回答 (3)
2007-10-15 4:14 am
✔ 最佳答案
1) y=2x/x-2y(x-2)=2x
xy-2y=2x
xy-2x=2y
x(y-2)=2y
x=2y/(y-2)
2) y=x+2/2-x
y(2-x)=x+2
2y-xy=x+2
2y-2=x+xy
x(1+y)=2y-2
x=(2y-2)/(1+y)
3) y=3x+1/x-1
y(x-1)=3x+1
xy-y=3x+1
xy-3x=1+y
x(y-3)=(1+y)/(y-3)
2007-10-15 4:27 am
1) y = 2x / x-2
xy - 2y = 2x
xy - 2x = 2y
x( y - 2) = 2y
x = 2y / y - 2
2) y = x+2/2-x
2y - xy = x + 2
2y - 2 = x + xy
2y - 2 = x ( 1 + y )
x = 2y - 2 / 1 + y
x = 2 ( y - 1 ) / 1+ y
3) y=3x+1/x-1
xy - y = 3x + 1
xy - 3x = 1 + y
x ( y - 3) = 1 + y
x = 1 + y / y - 3
xy - 2y = 2x
xy - 2x = 2y
x( y - 2) = 2y
x = 2y / y - 2
2) y = x+2/2-x
2y - xy = x + 2
2y - 2 = x + xy
2y - 2 = x ( 1 + y )
x = 2y - 2 / 1 + y
x = 2 ( y - 1 ) / 1+ y
3) y=3x+1/x-1
xy - y = 3x + 1
xy - 3x = 1 + y
x ( y - 3) = 1 + y
x = 1 + y / y - 3
2007-10-15 4:24 am
QUESTION1:
y=2x/x-2
y(x-2)=2x
xy-2y=2x
xy-2x=2y
x(y-2)=2y
x=2y/(y-2)
QUESTION2:
y=x+2/2-x
y(2-x)=x+2
2y-xy=x+2
2y-2=x+xy
x(1+y)=2(y-1)
x=2(y-1)/(1+y)
QUESTION3:
y=3x+1/x-1
y(x-1)=3x(x-1)+1
xy-y=3x^2-3x+1
3x^2-3x+1-xy=-y
3x(x-1+y)=-y-1
x(x-1+y)=(-y-1)/3
第3條有2次方....唔知岩唔岩..
y=2x/x-2
y(x-2)=2x
xy-2y=2x
xy-2x=2y
x(y-2)=2y
x=2y/(y-2)
QUESTION2:
y=x+2/2-x
y(2-x)=x+2
2y-xy=x+2
2y-2=x+xy
x(1+y)=2(y-1)
x=2(y-1)/(1+y)
QUESTION3:
y=3x+1/x-1
y(x-1)=3x(x-1)+1
xy-y=3x^2-3x+1
3x^2-3x+1-xy=-y
3x(x-1+y)=-y-1
x(x-1+y)=(-y-1)/3
第3條有2次方....唔知岩唔岩..
參考: ME
收錄日期: 2021-04-13 13:54:54
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20071014000051KK04917