题目内容
(1)分解因式:4x6y2+4x5y-24x6=_____________.
(2)分解因式:x2-16y2-8y-1=_____________.
(3)分解因式:x2-2xy+y2+2x-2y-8=_____________.
(4)分解因式:a2(b2-c2)-c2(b+c)(b-c)=_____________.
(5)分解因式:(x2+x-6)(x2+x-8)-24=_____________.
(6)若x2+mx+n是一个完全平方式,则m、n的关系是_____________.
(7)若18x2+mx+5=(9x-5)(2x-1),则m=_____________.
(8)若a+b=3,ab=-2,则a3+a2b+ab2+b3=_____________.
(9)a、b、c是△ABC的三边,且a2+b2+c2=ab+ac+bc,则△ABC是_____________三角形.
(10)已知a+=3,则a2+的值是_____________.
(11)若x2+3x-4=(x+a)(x+b),则的值是_____________.
(12)若4a2+9b2-4a+12b+5=0,则a=_____________,b=_____________.
已知:x=y+2,求[(x+y)(x-y)-(x-y)2+2y(x-y)]÷4y的值;
求下列分式的值:
(1)已知=,求的值;
(2)已知x∶2y∶3z=3∶4∶6,求的值.
已知代数式A=2x2+3xy+2y-1,B=x2-xy+x-
(1)当x=y=-2时,求A-2B的值;
(2)若A-2B的值与x的取值无关(含x项的系数为0),求y的值.