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(1)计算:2013×2015-2014×2014;(2)计算:(-13xy2)2-[xy(2x-y)+xy2];(3)分解因式:a2(x-y)+b2(y-x);(4)解不等式:(x+3)(x-7)+8>(x+5)(x-1);(5)解方程:(3x+2

题目详情
(1)计算:2013×2015-2014×2014;     
(2)计算:(-
1
3
xy2)2-[xy(2x-y)+xy2];
(3)分解因式:a2(x-y)+b2(y-x);     
(4)解不等式:(x+3)(x-7)+8>(x+5)(x-1);
(5)解方程:(3x+2)(3x-2)=(9x+5)(x-2)+15;     
(6)分解因式:3xy4-24xy2+48x.
▼优质解答
答案和解析
(1)原式=(2014-1)×(2014+1)-2014×2014
=2014×2014-1-2014×2014
=-1;
(2)原式=
1
9
x2y4-[2x2y-xy2+xy2]
=
1
9
x2y4-2x2y;
(3)原式=(a2-b2)(x-y)
=(a+b)(a-b)(x-y);
(4)(x+3)(x-7)+8>(x+5)(x-1)
x2-4x-21>x2+4x-5
-8x>16
x<-2;
(5)(3x+2)(3x-2)=(9x+5)(x-2)+15
9x2-4=9x2-13x-10+15
13x=9
x=
9
13

(6)原式=3x(y4-8y2+16)
=3x(y2-4)2
=3x(y+2)2(y-2)2