數學問題(如何拆解代數)快!!!!!!!謝!20點!!!!!
回答 (5)
2014-10-01 12:57 am
✔ 最佳答案
2(2X-4)=(2*2x)+[2*(-4)]=4x-8
a(b+c)=ab+acà乘法分配律
2014-10-04 5:00 am
其實只要記住:
a(b?c)=ab?ac
(a+b)`=a`+2ab+b`
(a+b)(a-b)=a`-b`
(a-b)`=a`+b`
PS.
`=Square(2次方)
&
? = + - * /
(中1夠用...我讀緊XD)
詳細D...
'.'
2(2x-4)=2x*2-2*(+4)
=4x-8
.'. We can know that a(b?c)=ab?ac
(a+b)`
=(a+b)(a+b)
=a(a+b)+b(a+b)
=a`+ab+ab+b`
=a`+2ab+b`
(a+b)(a-b)
=a(a-b)+b(a-b)
=a`-ab+ab-b`
=a`-b`
(a-b)`
=a(a-b)(-b)(a-b)
=a`-ab-ab+b`
=a`+b`
a(b?c)=ab?ac
(a+b)`=a`+2ab+b`
(a+b)(a-b)=a`-b`
(a-b)`=a`+b`
PS.
`=Square(2次方)
&
? = + - * /
(中1夠用...我讀緊XD)
詳細D...
'.'
2(2x-4)=2x*2-2*(+4)
=4x-8
.'. We can know that a(b?c)=ab?ac
(a+b)`
=(a+b)(a+b)
=a(a+b)+b(a+b)
=a`+ab+ab+b`
=a`+2ab+b`
(a+b)(a-b)
=a(a-b)+b(a-b)
=a`-ab+ab-b`
=a`-b`
(a-b)`
=a(a-b)(-b)(a-b)
=a`-ab-ab+b`
=a`+b`
參考: My own notes
2014-10-02 9:03 am
2(2X-4)
將佢折開,其實就好似3(6+5)=3*6+3*5
但係注意:+同-可以將一個式分開做項,所以以上我個例子有2項
=2(2X)-2(4)
就乘左去...
4X-8
只係咁昨...其實唔難
希望你會明我講咩...
將佢折開,其實就好似3(6+5)=3*6+3*5
但係注意:+同-可以將一個式分開做項,所以以上我個例子有2項
=2(2X)-2(4)
就乘左去...
4X-8
只係咁昨...其實唔難
希望你會明我講咩...
2014-09-30 7:34 pm
Expansion formula:
(a+b)(c+d)=a(c+d)+b(c+d)
=ac+ad+bc+bd
Suppose 2(2x-4) to (2+0)(2x-4),
(2+0)(2x-4)=2(2x-4)+0(2x-4)
=2(2x-4)
The formula applies to this type with all number of terms.
For example:
(a+b+c)(d+e+f+g)= a(d+e+f+g)+b(d+e+f+g)+c(d+e+f+g)
(a+b)(c+d)=a(c+d)+b(c+d)
=ac+ad+bc+bd
Suppose 2(2x-4) to (2+0)(2x-4),
(2+0)(2x-4)=2(2x-4)+0(2x-4)
=2(2x-4)
The formula applies to this type with all number of terms.
For example:
(a+b+c)(d+e+f+g)= a(d+e+f+g)+b(d+e+f+g)+c(d+e+f+g)
2014-09-30 3:18 am
因為要拆括號就要 2 乘括號內嘅 2 ，因為X跟住前面的 2 ，所以不用乘。 2 是正數，負正得負，(- + = -)所以 - 4 乘 2 就等於 - 8。答案就系 4X-8
收錄日期: 2021-04-15 16:40:28
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20140929000051KK00057