各位知識朋友 , 入黎幫下手呀!!!
我有數學問題唔識 , 幫手解答呀( 數學F.2 )!!!!!!!!!!!!!!! (要步驟)
1. Factorize
(a) - 343 - 8y^3
(b) ( x + y )^3 - 8(x - y)^3
2.
(a) Factorize x^2 - 2xy + y^2
(b) Hence simpfify x^2 - 2x(x + 1) + (x + 1)^2
3. Factorize a^2 + 2ab + 2a + (b + 1)^2
<40 m> F.2 因式分解 (3)
2009-07-12 5:48 am
回答 (1)
2009-07-12 6:14 am
✔ 最佳答案
1.(a)- 343 - 8y3
=-73-(2y)^3
=-[73+(2y)^3]
=-(7+2y)(49-14y+4y2)
(b)
( x + y )3 - 8(x - y)3
=( x + y )3 - [2(x - y)]3
=[(x+y)-2(x-y)][(x+y)2+2(x+y)(x-y)+(x-y)2]
=(-x+3y)[(x2+2xy+y2)+2(x2-y2)+(x2-2xy+y2)]
=(-x+2y)(4x2)
2.(a)x2- 2xy + y2
=(x-y)2
(b)x2- 2x(x + 1) + (x + 1)2
=[x-(x+1)]2
=12
=1
3.a2+ 2ab + 2a + (b + 1)2
=a2+ 2a(b+1) + (b + 1)2
=[a+(b+1)]2
=(a+b+1)2
收錄日期: 2021-04-23 20:42:54
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090711000051KK01839