5x-2y=1 x=7-3x
若2x-3y+4=0则x(x*x-1)+x(5-x*x)-6y+7
y=(x-1)(x-2)(x-3)(x-4)(x-5)(x-6)(x-7)(x-8)(x-9)(x-10)的导数在x=1
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
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!)+.
x+y=3 x+2y=9 3/x+1=y y-x=3 y=2x-3 y-3x=1 2(x+1)-y=6 7x-5y=-9
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
7x-3y/5=5x-y/3-x+y/2 x-1/5=y+1/3
{ x-y/7-x+y/10=1/2 {2(x-y)+5(x+y)=3
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
函数,y=3x/(x^2+x+1) ,x
函数y=3x/(x^2+x+1) (x
(2x+y-1)(2x-y+1)-(3x+y)(3x-y),其中x=5分之1,