請解答maths

3a{2}-a+9ab-3b
=a(3a-1)+b(3a-1)
=(3a-1)(a+b)

3t{2}-2t-1
=(t-1)(3t+1)

1t -1
3t +1
------------
3t{2} -3t+1t=-2t -1

2007-01-10 17:31:37 補充：
第一題係抽3b....打錯左答案係(3a-1)(a 3b)

2007-01-10 17:32:05 補充：
(3a-1)(a 3b)

1.3a{2}-a+9ab-3b
= a(3a-1)+3b(3a-1)
= (a+3b)(3a-1)//

2.3t{2}-2t-1
= (3t-1)(t+1) 3t -1
So, t = 1/3 or -1 t 1

2007-01-10 17:34:36 補充：
最尾係 t = 1/3 or t = -1

3a^2-a+9ab-3b
=a(3a-1)+3b(3a-1)
=(a+3b)(3a-1)


3t^2-2t-1
=(3t+1)(t-1)


^2=2次方