5x+7y-3x

用递归法求y=x-(x*x*x/3!)+(x*x*x*x*x/5!)-(x*x*x*x*x*x*x/7!)+. (3x-4y)(5x-4y)-(7x-8y)(6y-5x) 化简:3(x-y)²-7(x-y)+ 2(x-y)²+5(x-y) 计算(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-x^y^7+y^8)(x^2+xy+y^2) 3x+5y-(x+y)=6 2(x+y)-3x=-7 5x+7y-3x 5(x-y)³-3（x-y）²+7(x-y)-5(x-y)³+（x-y）²-5（x-y）,其中,x-y=1/3.5(x-y)³-3（x-y）²+7(x-y)-5(x-y)³+（x-y）²-5（x-y）,其中,x-y=1/3先化简,再求值； 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 （x+y-5)*（x+y-5)+（x-y+3)=0 x*x-y*y 已知:3x-5y=0,求x/y,x-y/y,x-y/x -(5x+y)-7(x-y) -2分之1（x+y）+4分之1（x+2y） 4x-2（x-2） -2x-（3x-1） x-(5x-2y)+2(2x-y) x+y=1 5x-2y=8 3x-y=7 2x-y=3x表示y和用y表示x 化简3(x-y)-7(x--y)+2(y-x) 化简:5(x-y)+2(x+y)-3(x-y) (y-x)(x-y)^3(y-x)^5怎么算 把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)= 3(x-y)把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)=3(x-y)²-4(x-y)+7(x-y)-6(x-y)²= 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) (2x+y)²+(x+3y)(x-3y)-x(5x+8y)因式分解