香港中學會考 - 2006 - 卷一 -

答案：(a) $b(3-a)$ (b) $(3+a)(3-a)$ (c) $(3-a)(3+a+b)$

1. $\be

答案：A
$\begin{array}{cl}
& pr+qr -ps-qs \\
= & r(

答案：B
I 並不是恒等式。設 $x=1$，

$\begin{array}{rcl}
\text{左方} �

答案：(a) $(r+5)^2$ (b) $(r+s+5)(r-s+5)$

1. $\begin{array}{c

答案：A
$\begin{array}{cl}
& (x+x)(y+y+y) \\
= & 2

答案：C
I 有因式 $x+y$。

$x^2-y^2=(x+y)(x-y)$

II 不能被因式分解。

III 有因式

答案：(a) $ab(a+b)$ (b) $(a+b)(ab+7)$

1. $\begin{array}{cl}
   &

答案：A
$\begin{array}{cl}
& (3x-5)(2x^2 + 5x -3) \\
= &#

答案：(a) $(m+6n)^2$ (b) $(m+6n+5k)(m+6n-5k)$

1. $\begin{arr

答案：B
$\begin{array}{cl}
& ab+ac-a^2-bc \\
= & a

答案：(a) $(9m+n)(9m-n)$ (b) $(9m-n)(9m+n+2)$

1. $\begin{arr

答案：D
$\begin{array}{cl}
& (x-2y)(x+2y-2) \\
= &

答案：(a) $(x-3y)^2$ (b) $(x-3y)(x-3y+7)$

1. $\begin{array}{

答案：D
$\begin{array}{cl}
& (4x+y)^2-(4x-y)^2 \\
= &#

答案：(a) $(2m+5n)(2m-5n)$ (b) $(2m-5n)(2m+5n+3)$

1. $\begin

答案：D
$\begin{array}{cl}
& h\ell -k\ell + hm – k