(2x+1)(x-y)-(3x+1)(x-y)
要最詳細既步驟
thx!!
中2數,因式分解一條 (20分)
2008-09-23 1:44 am
回答 (6)
2008-09-23 1:47 am
✔ 最佳答案
(2x+1)(x-y)-(3x+1)(x-y)=(x-y)(2x+1-3x-1)
=(x-y)(-x)
=-x(x-y)
參考: 我
2008-09-27 1:13 pm
上面好多個人都做錯數呀 題目話因式分解呀 唔係展開呀
(2x+1)(x-y)-(3x+1)(x-y)<--當中(x-y)係(2x+1)(x-y)&(3x+1)(x-y)都有既項
所以就要抽(x-y)出黎
如下
(2x+1)(x-y)-(3x+1)(x-y)
=(x-y)((2x+1)-(3x+1))
=(x-y)(2x+1-3x-1)
=(x-y)(-x)<--去左咁既樣呢,就要展開啦p.s(x-y)(單一個數)
=y-x
如果你仲係唔明既話,就將x-y當係a咁睇
設x-y為a
(2x+1)(x-y)-(3x+1)(x-y)
=(2x+1)a-(3x+1)a
=a((2x+1)-(3x+1))
=a(2x+1-3x-1)
=a(-x)<--而家先將(x-y)代返入去a都得,方便你計就得
仲係唔識就聯絡我啦
[email protected]
(2x+1)(x-y)-(3x+1)(x-y)<--當中(x-y)係(2x+1)(x-y)&(3x+1)(x-y)都有既項
所以就要抽(x-y)出黎
如下
(2x+1)(x-y)-(3x+1)(x-y)
=(x-y)((2x+1)-(3x+1))
=(x-y)(2x+1-3x-1)
=(x-y)(-x)<--去左咁既樣呢,就要展開啦p.s(x-y)(單一個數)
=y-x
如果你仲係唔明既話,就將x-y當係a咁睇
設x-y為a
(2x+1)(x-y)-(3x+1)(x-y)
=(2x+1)a-(3x+1)a
=a((2x+1)-(3x+1))
=a(2x+1-3x-1)
=a(-x)<--而家先將(x-y)代返入去a都得,方便你計就得
仲係唔識就聯絡我啦
[email protected]
參考: 教科書
2008-09-24 2:14 am
(2x+1)(x-y)-(3x+1)(x-y)
=(x-y)(2x+1-3x-1)
=(x-y)(-x)
=-x(x-y)
=-x^2+xy
=(x-y)(2x+1-3x-1)
=(x-y)(-x)
=-x(x-y)
=-x^2+xy
參考: MYSELF
2008-09-23 2:00 am
(2x+1)(x-y)-(3x+1)(x-y)
= 2x*-y-3x*+y
= -x*
注意: *=2
# 首先, 將2x乘x, =2x* (x乘x=x*), 接著1乘-y=-y.
同道理, -3x乘x=-3x*, -1乘-y=y.接下來你應該識La!
= 2x*-y-3x*+y
= -x*
注意: *=2
# 首先, 將2x乘x, =2x* (x乘x=x*), 接著1乘-y=-y.
同道理, -3x乘x=-3x*, -1乘-y=y.接下來你應該識La!
參考: 自己
2008-09-23 1:51 am
(2x+1)(x-y)-(3x+1)(x-y)
2 2
=2x +X-2xy-y-3x +x+3xy-y
2
=-x +2x+xy-2y
最詳細既步驟!!!!!!!!
2 2
=2x +X-2xy-y-3x +x+3xy-y
2
=-x +2x+xy-2y
最詳細既步驟!!!!!!!!
參考: me
2008-09-23 1:49 am
(2x+1)(x-y)-(3x+1)(x-y)
=(x-y)[(2x+1)-(3x+1)]
=(x-y)(2x+1-3x-1)
=(x-y)(-x)
=-x^2+xy
=(x-y)[(2x+1)-(3x+1)]
=(x-y)(2x+1-3x-1)
=(x-y)(-x)
=-x^2+xy
收錄日期: 2021-04-15 17:12:49
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