化简并求值,已知x.y满足3x 5y=1
来源:学生作业帮助网 编辑:作业帮 时间:2024/11/08 21:55:11
再问:大神,你写给我吧再问:WiFi不行,图片看不了再答:我不是写了?
原式=y2-2y+1,当y=-1时,原式=y2-2y+1=(-1)2-2×(-1)+1=4.
是(x-2)²+|y+1|=0所以x-2=0,y+1=0x=2,y=-1所以原式=-9y+6x²+3y-2x²=-6y+4x²=6+16=22
X^2+Y^2-4X+6Y+13=0(x-2)^2+(y+3)^2=0x=2,y=-3(3X+Y)^2-3(3X-Y)(X+Y)-(X-3Y)(X+3Y)=9x^2+6xy+y^2-3(3x^2+2x
3(x-2y)-2(3x-y)=3x-6y-6x+2y=-3x-4y=3-2=1再问:1是求值的结果还是化简的再答:=-3x-4y是化简的结果=1是求值的结果
(2X+3Y)²-(2X+Y)(2X-Y)=4X²+12XY+9Y²-(4X²-Y²)=4X²+12XY+9Y²-4X²
(x+2y)(2x+y)-(3x-y)(x+2y)=(2x^2+5xy+2y^2)-(3x^2+5xy-2y^2)=4y^2-x^2=1-81=-80
原式=9x2+6xy+y2-3(3x2+3xy-xy-y2)-(x2-9y2) =9x2+6xy+y2-9x2-6xy+3y2-x2+9y2 &
∵x2+y2+54=2x+y,∴x2-2x+1+y2-y+14=0,∴(x-1)2+(y-12)2=0,∴x=1,y=12,当x=1,y=12时,原式=1×121+12=13.故答案是13.
即(x²-4x+4)+(y²+6y+9)=0(x-2)²+(y+3)²=0所以x-2=y+3=0x=2,y=-3原式=9x²+6xy+y²-
4x^3(-y^3)^2-3x*(-x)^2(-y^2)^3=4x^3y^6+3x^3y^6=7x^3y^6=7*(-3)^3*(-2)^3=1512
(x+y)+(2x+y/2)+(3x+y/2*3)+(4x+y/3*4)+.+(8x+y/8*9)=(x+2x+3x+...+8x)+y[1+(1/2)+1/(2×3)+1/(3×4)+...+(1/
x=2y=1
|x-2|+(y+3)²=0都是非负式所以分别都=0所以x-2=0y+3=0所以x=2y=-3又因为z是最大的负整数所以z=-1原式=2(x²y+xyz)-3(x²y-x
2x-y=3mx+2y=4m+5x+y=91式乘以a+2式乘以b凑成3式,因此2a+b=1-a+2b=13m*a+(4m+5)*b=9a=1/5b=3/5(3/5)m+3*(4m+5)/5=93m+3
1.x<0,y>0,|x|<y∴-y<x<y∴0<x+y<2y-2y<x-y<0...∴|x+y|+|x+(-y)|+2(-y)=x+y-x+y-2y=02.x-7=0y+13
已知x.y.z满足/x-2/+(y+3)^2=0,z是最大的负整数.x-2=0;x=2;y+3=0;y=-3;z=-1;化简求值:2(x^y+xyz)-3(x^2y-xyz)-4x^y=2x^y+2x
x²+y²-4x+6y+13=0(x-2)²+(y+3)²=0x=2,y=-3(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)=(6
5x=-3yx=-3|5y直接带进去得答案,或者=2\3x-2|3x+2|x+y的和乘(x+y)除以x-y|x=2乘x\x-y=2(-3\5y)\(-3\5y-y)=3\4手机果然不行.
(x+y)x+(x-y)x-(6x^2y-2xy^2)除以(2y)=2x^2-(3x^2-xy)=xy-x^2=(-2)*1/3-(-2)^2=-14/3