Please help me!too easy...but I don't know...

(4a+b)2+(4a+b)(-3a-2b)+(4a+b)(b-a)
= (4a+b) (2-3a-2b+b-a)
= (4a+b) (2-4a-b)







希望幫到你.

2007-10-11 21:21:05 補充：
{ 抽common factor :(4a b) }

2007-10-12 23:11:44 補充：
幫到你嗎?

2007-10-17 15:11:41 補充：
Should be:4a b)2 (4a b)(-3a-2b) (4a b)(b-a) = (4a b)(4a b) (4a b)(-3a-2b) (4a b)(b-a) = (4a b) (4a b-3a-2b b-a)………. { 抽common factor (4a b) }= (4a b) (0)= 0Hope can help you.

2007-10-17 15:22:17 補充：
cos plus/minus did not show, email ans again to you.

(4a+b)2+(4a+b)(-3a-2b)+(4a+b)(b-a)
= 8a + 2b + 4a(-3a - 2b) + b(-3a - 2b) + 4a(b - a) + b(b - a)
= 8a + 2b - 12a^2 - 8ab - 3ab - 2b^2 + 4ab - 4a^2 + b^2 - ab
= -12a^2 - 4a^2 - 2b^2 + b^2 - 8ab - 3ab + 4ab - ab + 8a + 2b
= -16a^2 - b^2 - 8ab + 8a + 2b