已知(x-y)∧3=x∧3-3x∧2y+3xy∧2-y∧3对任意x,y都成立.(1)填空:(x-y)(x+y)(x+y)
已知(x-y)∧3=x∧3-3x∧2y+3xy∧2-y∧3对任意x,y都成立.(1)填空:(x-y)(x+y)(x+y)
若对任意x+y+3=xy(x>0,y>0)的任意x,y (x+y)^2-a(x+y)+1≥0恒成立
若对满足条件x+y+3=xy(x>0,y>0)的任意x,y,(x+y)2-a(x+y)+1≥0恒成立,则实数a的取值范围
已知函数f(t)对任意实数x,y都有f(x+y)=f(x)+f(y)+3xy(x+y+2)+k(x+y)+3,k为常数,
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y
已知xy=2,x-y=3,求(x+y)(x-y)-y^2-(6x^2y-2xy^2)/2y的值.
已知xy=-2,x-y=3,求(x+y)(x-y)-y平方+(x-y)平方-(6x2y-2xy平方)/2y的值
已知x-5y=0,求分式x²-2xy+y²/3x+y × (y-x)的值
初中数学分式已知x/y=2,求(x*x-xy+3y*y)/x*x+xy+6y*y的值
已知x-y=1,y≠0,求{(x+2y)²+(2x+y)(x+4y)-3(x+y)(x-y)}÷y的值.
已知:(x+2)²+|x+y-10|=0,求3x²y-[5x²y-﹙2xy-x²
已知(x+2)^2+|x+y+5|=0,求3x^2y-[2x^2y-(2xy-x^2y)-4x^2]-xy