f.2 MATHS (急!!!!!) (40points)

1) (a-b)^2-(a-b)
=(a-b)(a-b-1)

2) 8a(x-2)+6b(2-x)
=(x-2)(8a-6b)
= 2(x-2)(4a-3b)

3) 4m(x-y)-24n(y-x)
=4(x-y)(m+6n)

4) 5a-5b+2acd-2bcd
=a(5+2cd)-b(5+2cd)
=(a-b)(5+2cd)

5) 4p^2-3q-3p+4pq
=p(4p-3)+q(4p-3)
=(4p-3)(p+q)

6)81a^4-16b^4
=(9a^2-4b^2)(9a^2+4b^2)
=(3a-2b)(3a+2b)(9a^2+4b^2)

7) x^3+4x^2+4x
=x(x^2+4x+4)
=x(x+2)(x+2)

8) 2x^3+8x^2+8x-18xy^2
=x(2x^2+8x+8-18y^2)
=x(x+2)(x+2)-18xy^2
=x((x+2)(x+2)-18y^2)

9) (3x+1)^2-(3x-1)^2
=(3x+1+3x-1)(3x+1-3x+1)
=(6x)(2)
=12x

10) ay-2by-4ax+8bx
=y(a-2b)-4x(a-2b)
=(a-2b)(y-4x)

11) simplify:

3ax+5ay-6bx-10by
=a(3x+5y)-2b(3x+5y)
=(3x+5y)(a-2b)


----------------------------
ay-2by-4ax+8bx
=y(a-2b)-4x(a-2b)
=(a-2b)(y-4x)

8) 2x^3+8x^2+8x-18xy^2
= 2x (x^2+4x+4) - 18xy^2
= 2x [(x+2)^2 - 9y^2]
= 2x (x+9y+2)(x-9y+2)

2007-04-19 00:37:39 補充：
1-7 , 9-11題的意見同其他人一樣