神马作文网(x y)(x-y) 4(y-1)= 分解因式
来源：学生作业帮助网 编辑：作业帮 时间：2024/11/18 16:07:02
(x+1)(y+1)
x+y=3,xy=14x+3xy+4y=4(x+y)+3xy=4x3+3x1=12+3=15祝学习进步,望采纳,不懂的欢迎追问.再问：怎么又是你啊。。。再问一道题：代数式x²＋x＋3的值为7
(x+y-2xy)(x+y-2)+(1-xy)^2=(x+y)^2-2(1+xy)(x+y)+4xy+1-2xy+x^2y^2=(x+y)^2-2(1+xy)(x+y)+(1+xy)^2=(x+y)^
xy-1+x-y=XY+X-Y-1(加法交换律）=（XY+X）－（Y＋1）＝X（Y＋1）－(Y+1)（提取公因式X）=(Y+1)(X-1)（提取公因式Y+1）这样可以么?
(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)=-6xy+3x-3y=-6×(-2)+3×1=15
原式=3x-3y-6xy=3-12=-9
1-x-y+xy=(1-x)-(y-xy)=(1-x)-y(1-x)=(1-x)(1-y)
(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)=-2xy+2x+3y-3xy-2y+2x-x-4y-xy=-6xy+3x-3y=-6xy+3*(x-y)当时,原式=-6*1+3*
xy+1/xy+y/x+x/y=[(xy)^2+1+x^2+y^2]/(xy)=[(xy)^2-2xy+1+x^2-2xy+y^2+4xy]/(xy)=[(xy-1)^2+(x-y)^2+4xy]/(
（x+y)*(x+1)-y(x+y)=(x+y)*(x+1-y)
xy-x-y+1=x(y-1)-y+1=x(y-1)-(y-1)=(y-1)(x-1)
xy+1/xy>=2√（xy*1/xy）=2(当xy=1/xy即xy=1时取等号)x/y+y/x>=2√（x/y*y/x）=2(当x/y=y/x即x=y取等号)当x=y=1时可以同时满足两项的等号要求
(X-1/2Y)方
（-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)=(-2xy-3xy-xy)+(2x+2x-x)+(3y-2y-4y)=-6xy+3x-3y=-6+3*3=3
x²+xy/(x-4y)(x+y)=x(x+y)/(x-4y)(x+y)=x/(x-4y)=4/(4+4)=1/2
(x-1)(y-1)
x^2y+4xy+4y=y(x²+4x+4)=y(x+2)²
解:原式=xy+y-x-1=y(x+1)-(x+1)=(x+1)(y-1)
原式={[(x-y)^2+4xy]/(x-y)}{[(x+y)^2-4xy]/x+y}={[x^2-2xy+y^2+4xy]/(x-y)}{[x^2+2xy+y^2-4xy]/x+y}={[x^2+2
(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)=-2xy+2x+3y-3xy-2y+2x-x-4y-xy=-6xy+3x-3y=-6*(-2)+3*1=15不懂可追问,有帮助请采