设实数x,y,m,n满足x^2+y^2=3,m^2+n^2=1,若a≥mx+ny恒成立,求a的取值范围

设实数x,y,m,n满足x^2+y^2=3,m^2+n^2=1,求mx+ny的最大值． 设实数x,y,m,n满足x^2+y^2=3,m^2+n^2=1 ,则mx+ny的最大值为 设实数x,y,m,n满足 x^2+y^2=1,m^2+n^2=1,则mx+ny的取值范围 设实数x,y满足 x>=0 x-2y>=0 x-y-2 设实数x,y满足约束条件：x>=2;y>=x;2x+y 设实数X,Y满足X^2-2X-4Y=5,M=X-2Y,求M的取值范围 设实数x,y满足方程组①x-y-2=0 ③2y-3 设实数X,Y满足2X+Y-2>=0,X-2Y+4>=0,3X-Y 设实数x,y 满足x²+4y²+2x-4y+2+0 则x+y= 设正实数x,y满足x^3+y^3=x-y,求证：x^2+4y^2 设Z=x+y,其中实数x,y满足不等式x+2y>=0,x-y 设z=x+y,其中实数x,y满足{x+2y>=0,x-y 设实数x、y满足方程2x^2+3y^2=6y,求x+y的最大值 设实数x、y满足方程2x²+3y²=6y,求x+y的最大值 设实数x,y满足y+x^2=0,0 设实数x.y满足y+x^2=0,若0 ·设实数x,y满足y+x^2=0,若0 设实数x,y满足y+x^2=0,0