y=(4x^2-7)(2-x)
若2x-3y+4=0则x(x*x-1)+x(5-x*x)-6y+7
已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),求x,y
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
y=4x^2-5x+7/x-2(x>2),求y最值
4x-(2x+y+16)/2=-6y 2x+3y=7-x-2y
方程2分之x+y+2分之x-y=7,4(x+y)-5(x-y)=2
解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
已知4x=9y求(1)x+y/y (2)y-x/2x
若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于
x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20
{(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20