X△Y=2X-Y,A⊕B=A-B/2,则3△(4⊕1)=() 答案找到了,X△Y=2X-Y,A⊕B=A-B/2,则3△(4⊕1)=()3△(4⊕1)=3△(4-1/2) 为什么这里就变成1/2了,=3△7/2=2*3-7/2=5/2=3△(4-1/2)=3△7/2=2*3-7/2=5/2'

集合A={(x,y)|x-2y=1}B={(x,y)|x+3y=6},则A∩B= A∪B=? 向量a,b,x,y满足关系:a=y-x,b=2x-y,|a|=|b|=1,a*b=0,则|x|+|y|等于多少向量a,b,x,y满足关系：a=y-x,b=2x-y,|a|=|b|=1,a*b=0,则|x|+|y|等于多少 若集合A={(x,y)|y>=|x-2|} ,B={(x,y)|y A={（x,y)|y>=0.5|x-2|},B={(x,y)|y 定义新运算：x*y=(x+2y)/(x-y),则a*b×[b*(-a)]=______________ 若-4x^a y+x^2 y^b=-3x^2 y,则a+b等于? 已知a,b,X,Y属于R+,求证a^2/X+b^2/Y>=(a+b)^2/(X+Y) 已知3x+2y=a,2x+3y=b,则(x+y)(x-y)=? 已知：A=X*X-3xy+y*y,B=2x*x+xy-3y*3y.求A+B,A-B,A+2B 已知实数a,b,x,y,满足不等式（a+b）(x+y)>2(ay+bx),求证（x-y）/(a-b)+(a-b)/(x-y)>=2 通分 a/(y-x)^2,b/(x-y)(x+y) 因式分解a(x-y)+b(y-x)+(2x-y) 若集合A={(x,y)|y=2^x,x>0},B={y|y=lg(2x-x^2)},则A∩B= 已知x=y,则下面变形错误的是 A.x+a=y+a B.x-a=y-a C.2x=2y已知x=y,则下面变形错误的是 A.x+a=y+a B.x-a=y-a C.2x=2y D.x/a=y/a 初一因式分解练习题,谁好心帮我解下表示平方1.2X~-3XY-X2.(X+Y)~(X+Y)(X-Y)(X+Y)(Y+Z)3.3X(a+2b)~-6XY(a+2b)4.a(x-y)-b(X-Y)-C(Y-X)5.(b-a)~-2a+2b6.(x-y)~-m(y-x)+y-x7.x(x-y)(a-b)-y(y-x)(b-a)8.已知a+b=13,ab=40,求 b+ab~的值 抛物线y=2-(x-a)(x-b)(a 填空：(b-a)(2x-y+1)=(a-b)( ) A={(X,Y)|X+Y>=1},B={(X,y)|X^2+y^2=1},B={(X,y)|X^2+y^2