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(1)(X2-5X+2)(X2-5X+4)-8(2)a2*(m+n)3-a2b3(3)6X2-7X-3(4)7(a+b)2-5(a+b)-2(5)3ax-3ay+xy-y2(6)5x2-15x+2xy-6y(7)x6-y6-2x3+1

题目详情
(1)(X2-5X+2)(X2-5X+4)-8
(2)a2*(m+n)3-a2b3
(3)6X2-7X-3
(4)7(a+b)2-5(a+b)-2
(5)3ax-3ay+xy-y2
(6)5x2-15x+2xy-6y
(7)x6-y6-2x3+1
▼优质解答
答案和解析
(1)(X2-5X+2)(X2-5X+4)-8
=(x*x-5x)(x*x-5x)+6(x*x-5x)+8-8
=(x*x-5x)(x*x-5x+6)
=x(x-5)(x-2)(x-3)
(2)a2*(m+n)3-a2b3
=a2[(m+n)3-b3 ]
=a2(m+n-b)[(m2+2mn+n2+bm+bn+b2)
(3)6X2-7X-3
=(3X+1)(2X-3)
(4)7(a+b)2-5(a+b)-2
=[7(a+b)+2][(a+b)-1]
=(7a+7b+2)(a+b-1)
(5)3ax-3ay+xy-y2
=3a(x-y)+y(x-y)
=(x-y)(3a+y)
(6)5x2-15x+2xy-6y
=5x(x-3)+2y(x-3)
=(x-3)(5x+2y)
(7)x6-y6-2x3+1
=(x3-1)2-y6
=(x3-1+y3)(x3-1-y3)