求Y=2X*2-3X+5,在【-2,2】上的极值

已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? 求y =2^x -1/x+1在x 5X+Y=3 X+5Y=2 求x和y.5X+Y=3X+5Y=2求x和y. y=x^3-5x^2+2x-8 求y^2求y撇 6x+5Y=31 2X+3Y=17求X求 Y 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 求(X+Y)(X-Y)(X²+Y²),X=5 Y=2, 已知|x|=2,|y|=3,|x+y|=-(x+y)求x-y 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 y=3(x-y),x=2(x-y)求x,y的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² 若x-y/x+y=5,求x-y/2x+2y+5x+5y/3x-3y的值 若x+y分之x-y=3,求式子x+y分之5(x-y)—2(x-y)分之x+y的值 若x-y分之x+y=3,求式子x+y分之5(x-y)—2（x-y）分之x+y的值 3X+2Y=5X+2 2(3X+2Y)=2X+8 求 X Y 已知7x+5y/2y-x=3/2,且x≠0,求X/x-4y