✔ 最佳答案
1. 2 ( p + q )² - 6 ( p + q )³
2(p+q)² - 6(p+q)³
= (p+q)²[2 - 6(p+q)]
= 2(p+q)²[1 - 3(p+q)]
= 2(p+q)²(1-3p-3q)
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2. ( a - 2b)² + ( 2a - b )( 2b - a )
(a-2b)² + (2a-b)(2b-a)
[-(a-2b)]² + (2a-b)(2b-a)
= (2b-a)² + (2a-b)(2b-a)
= (2b-a)[(2b-a) + (2a-b)]
= (2b-a)(2b-a+2a-b)
= (2b-a)(a+b)
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3. 2 ( x + y - 1 )² - 4 ( 1 - x - y)
2(x+y-1)² - 4(1-x-y)
= 2(x+y-1)² + 4(x+y-1)
= 2(x+y-1)[(x+y-1) + 2]
= 2(x+y-1)(x+y+1)
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4. 18 ( 2a - 3b )² - 6 ( 3b - 2a)
18(2a-3b)² - 6(3b-2a)
= 6[3(2a-3b)² - (3b-2a)]
= 6[3(2a-3b)² + (2a-3b)]
= 6(2a-3b)[3(2a-3b)+1]
= 6(2a-3b)(6a-9b+1)
2007-01-02 10:28:19 補充:
下面的?不用照 copy 吧 -_-