1、9(2x-y)²-16(x+2y)² 2、-14xy-x²-49y² 3、(
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/10/06 23:38:44
1、9(2x-y)²-16(x+2y)² 2、-14xy-x²-49y² 3、(x²-2x)²-2x(2-x)+1
解
9(2x-y)²-16(x+2y)²
=[3(2x-y)-4(x+2y)][3(2x-y)+4(x+2y)]
=(6x-3y-4x-8y)(6x-3y+4x+8y)
=(2x-11y)(10x+5y)
=5(2x-11y)(2x+y)
-14xy-x²-49y²
=-(x²+14xy+49y²)
=-(x+7y)²
(x²-2x)²-2x(2-x)+1
=(x²-2x²)²+2(x²-2x)+1
=[(x²-2x)+1]²
=(x²-2x+1)²
=[(x-1)²]²
=(x-1)^4
9(2x-y)²-16(x+2y)²
=[3(2x-y)-4(x+2y)][3(2x-y)+4(x+2y)]
=(6x-3y-4x-8y)(6x-3y+4x+8y)
=(2x-11y)(10x+5y)
=5(2x-11y)(2x+y)
-14xy-x²-49y²
=-(x²+14xy+49y²)
=-(x+7y)²
(x²-2x)²-2x(2-x)+1
=(x²-2x²)²+2(x²-2x)+1
=[(x²-2x)+1]²
=(x²-2x+1)²
=[(x-1)²]²
=(x-1)^4
x-y/x²÷x²-2xy+y²/xy*(xy-x²)
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)
计算(1)3x/8y×16y²/27x² (2)(2xy-x²)÷x-2y/xy 2x-6
计算3x[xy-2x(1/y-x/3]+3y(x²-y²)
1、9(2x-y)²-16(x+2y)² 2、-14xy-x²-49y² 3、(
2x²-3xy=y²=0(x,y不得o)求x/y+y/x
化简 (x+y)(x²-xy+y²) ; 3(2x-1)(x+6)-5(x-3)(x+6)
计算3x/8y×16y²/27x² (2xy-x²)÷x-2y/xy 2x-6/x
化简求值[1-(2x/x+y)]÷ (x²-2xy+y²/3x+3y)+(x²+xy/x&
急![(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)
已知2X-3√xy-2y=0(x>0)求2x²+xy-9y²分之x²+4xy-16y
分式计算:(x²+2xy+y²)/(x²y+xy)*y/(x+y)