help me! form1數學

設最小數為Ｑ。

[Ｑ＋(Ｑ＋１)＋(Ｑ＋２)]-４Ｑ＝１
Ｑ＋Ｑ＋１＋(Ｑ＋２)-４Ｑ＝１
Ｑ＋Ｑ＋１＋Ｑ＋２-４Ｑ＝１
３Ｑ＋１＋２-４Ｑ＝１
３Ｑ-４Ｑ＝１－１－２
-１Ｑ＝-２
-Ｑ＝-２
Ｑ＝２

-Ｑ＝-２
點解變左
Ｑ＝２
因為負負得正

let xbe the smallest number

(x+x+1+x+2)-4x=1

3x+3-4x=1

x=2

the three are 2,3and4



Prove :

2+3+4-=9
2*4=-8
9-8=1

2006-10-28 16:47:30 補充：
2*4=-8not -8,is 8

設三個數中, 最小的為x
(x + x+1 + x+2)-4x = 1
(3x+3)-4x = 1
3-x = 1
3-x+x-1 = 1+x-1--------(兩邊加入 x-1)
3-1 = x
x = 2

該三個連續數為 2,3,4

Let X be the smallest number
X+X+1+X+2-4X=1x
x=2

2,3,4

let x be the smallest number
the three numbers are x,(x+1), and (x+2)
x+(x+1)+(x+2)-4x=1
3x+3-4x=1
-x=-2
x=2

so the smallest number is 2
the three numbers are 2, 3 and 4