2 (X-2Y)的平方-7(X-2Y)的立方-搜答案-搜搜考试网

1.运用平方差公式,原式=（3x-5+2x+7）(3x-5-2x-7)=(5x+2)(x-12)=5x的平方-58x-242.原式=（x的平方-4）的平方=x的4次方-8x的平方+163.原式=[2x

=x²-16x²+25y²+4x²+28xy+49y²=-11x²+28xy+83y²

(x平方-y平方)/(x+y)+(x平方-2xy+y平方)/(x-y)=(x+y)(x-y)/(x+y)+(x-y)^2/(x-y)=x-y+x-y=2(x-y)

x^2=x的平方‘/’为除以[(x+2y)^2-(x+y)(x-y)-5y^2]/(2x)=[(x^2+4xy+4y^2)-(x^2-y^2)-5y^2]/(2x)=[4xy]/(2x)=2y[(3x

4x^2-3y^2=73x^2+2y^2=19相加7x^2-y^2=26所以14x^2-2y^2=2(7x^2-y^2)=2*26=52

2(y-x)²-7(x-y)+6(x-y)-3(y-x)²=-(y-x)²-(x-y)=-(x-y)²-(x-y)=-(x-y)[(x-y)+1]=(y-x)(

x²-y²=(x+y)(x-y)所以最简公分母(x+y)²(x-y)所以2xy/(x+y)²=2xy(x-y)/(x+y)²(x-y)x/(x&sup

2xy/(x+y)的平方=2xy(x-y)/(x+y)²(x-y)x/x的平方-y的平方=x(x+y)/(x+y)²(x-y)

=8x²-16y²-7x²-xy+xy=x²-16y²

题目没有说明是化简还是分解因式,如果是化简的话,就是：7(x+y)²-5(x+y)²-2(x+y)=2(x+y)²－2(x+y)=2(x²＋2xy＋y²

3x的平方-【7y-2（4x的平方-y）-2x的平方】=3x²-[7y-8x²+2y-2x²]=3x²-7y+8x²-2y+2x²=13x&

(x-y)平方+2y(x-y)=(x-y)(x-y+2y)=(x-y)(x+y)

（x+y)(x-y)+(x-y)的平方-(6X的平方Y-2XY的平方）/2Y=x²-y²+x²-2xy+y²-3x²+xy=-x²-xy

设：(x+1)^2+2=t,则：y=(t-11)/(t)=1-11/t,(t≥2）当t趋于无穷大时,y趋于1；t=2时,y=-4.5.又∵函数明显单调递增,∴函数值域为[-4.5,1)

【2（x-y）²-8（x-y)²（x+y）+6y（x-y）²】÷2（x-y）²=2（x-y）²÷2(x-y)²-8（x-y)²（x

x(x+y)(x-y)-2x(x+y)=x(x(x-y)+y(x-y))-(2x^2+2xy)=x(x^2-xy+xy-y^2)-2x^2-2xy=x(x^2-y^2)-2x^2-2xy=x^3-xy

x8＋256y8-32x4y4(用手机打的不要介意,给个最佳答案吧）

∵4x²-y²+2x-y=(2x-y)(2x+y)+(2x-y)=(2x-y)(2x+y+1)∴4x²-y²+2x-y=(2x-y)(2x+y+1)不懂得欢迎追

x的平方-x-4y的平方+2y=(x-2y)(x+2y)-(x-2y)=(x-2y)(x+2y-1)

(x平方+2xy+y的平方）/（x+y)=（x+y)²/(x+y)=x+y