(4x-9y^(-1))/(2x^(1/2)+3y(-1/2))等于?SORRY 应该是(4x-9y^(-1))/(2x^(1/2)+3y^(-1/2))

4(x-y+1)+y(y-2x)4x^4-13x²+9 9y=3x-(x-1),4(x+y)-(2x+4)=8y x²/xy-x/y 3x/4x+y - x-2y/4x+y (1-y/y+x)÷x/y²-x² 1.(x^3-x^2-4x+1)/(x^2-3x+2)-(x^3-2x^2-9x+21)/（x^2-5x+6）+（x^2-3x+8）/（x^2-4x+3）2.{(x^2)/（x-y)}*{y/(x+y)}-{(x^4y)/(x^4-y^4)}÷{（x^2/x^2+y^2）^2} 化简 x-[y-2x-(x-y) -9-4[2x-5(x+1)] 2x-3{y-[3x-(2y-x)]-2x}过程一步一步的列好x-[y-2x-(x-y) -9-4[2x-5(x+1)] 2x-3{y-[3x-(2y-x)]-2x} (x-y)/4+(x+y)/5=1/4 (x+y)/9-(x-y)/3=//2(x-y)/4+(x+y)/5=1/4(x+y)/9-(x-y)/3=//2 1.4(x-2)^2-9(x+1)^22.x^2-4y^2-x+2y 已知4x=9y求(1)x+y/y (2)y-x/2x有关比例的 解二元一次方程 {3(x+y)-4(x-y)=-9 x+y/2+x-y/6=1 因式分解 （1）.(x+y)(x+y-6)+9 （2）.x²-16y²-x-4y 因式分解：-1/2*x*x*x*y+1/4*x*x*y*y-1/8*x*x*x*y*y*y {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 (x+y)(x-y)+4(y-1) 试说明（4x*x-7X+6Y--1）-（-2x*x+3y*y+2Y+2X)+(-6X*X+9X-Y)的值于X无关. 1/(x-y)+1/(x+y)+2x/(x^2+y^2)+4x^3/(x^4+y^4)化简 化简：[(2x-y)平方+（2x+y)(2x-y)-4x(x-y+1)]÷2x 把(x+y),(x-y)个作为一个整体合并同类项1,7(x+y)-2(x+y)-4(x+y)+2(x+y)2,(x-y)²＋2(x-y)－(x-y)－2(x-y)² 几道分式求值 速度 马上就要1. 1/x-y + 1/x+y + 2x/x^2+y^2 + 4x^3/x^4+y^4 + 8x^7/y^8-x^82. x-8/x-9 - x-7/x-8 - x-5/x-6 + x-4/x-53. 1/x^2+3x+2 + 1/x^2+5x+6 + 1/ x^2+4x+34. 1/x^2+2x-1 - 2/x^2+2x+1 + 1/