若2^x 4^y=1/2则x+2y取值范围抱歉。是2^x+4^y=1/2求x+2y取值范围

若x+y=4,则多项式1/2(x+y)+4(x-y)-3（x-y）-3/2(x+y)-x+y值是（） x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 若x,y,z成等差数列,则(z-x)^2-4(x-y)(y-x)= 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 若x=-1/4,能否确定代数式(2x-y)(2x+y)+(2x-y)(y-4x)+2y(y-3x)的值? 若x-y=1 化简（x+y)(x^2+y^2)(x^4+y^4)(x^8+y^8)(x^16+y^16) 若实数X,Y满足X²+Y²+4X-2Y +1=0,则X²-6X+Y²-2Y的最大值是多少 若f(x+y,y/x)=x^2-y^2,则F(X,Y)= 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 若x*x+y*y=x+y-1/2,求x,y的值如题 若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*y)的值 若x+y=1,x不等于0则x+(2xy+y^2)/x/(x+y)/x= 已知x*x+4x+y*y-2y+5=0,则x*x+y*y=? x+y+2(-x-y+1)=3(1-y-x)-4-(y+x-1),x+y=? 若2x=3y,则(x*x+y*y)/x*x=? 若x=2012,y=2013,则(x+y)×[(x^2+y^2)/x^4-y^4)]