七年级xy 2y=4y-3xy
来源:学生作业帮助网 编辑:作业帮 时间:2024/04/19 19:51:44
﹙1﹚原式=2x+3y-2xy-x-4y-xy-3xy-2y+2x=3x-3y-6xy=3﹙x-y﹚-6xy=3×2^2009-6×3^2010=3^2010-6×2^2010=﹣5×3^2010.﹙
因为绝对值和平方的结果都不小于0,因此只有两部分都为0时才成立X-1=0,X=1XY-2=0,XY=2,Y=21/(1×2)=1/1-1/2,1/(2×3)=1/2-1/3,1/(3×4)=1/3-1
1.2(Xy+Xy)-3(Xy-xy)-4Xy=2*2xy-0-4xy=4xy-4xy=02.1/2ab-5aC-(3acb)+(3aC-4aC)=1/2ab-5ac-3acb-ac=1/2ab-6a
xy/(2x+y)-xy/(2x-y)=3xy/(2x-y)+xy/(2x+y)=4;一、两公式对加得2xy/(2x+y)=7xy=(2x+y)*7/2二、把xy代入原公式求解就行了:(2x+y)*7
x^+2xy+y^+4=16(x+y)²=16-4=12(1)x^-2xy+y^=16(x-y)²=16(2)(1)-(2)2y*2x=-4xy=-1(3xy+6y^)+|x^-(
因为x-y=4xy所以x-2xy-y=2xy2x+3xy-2y=11xyx-2xy-y分之2x+3xy-2y=5.5
(-3x^y+2xy)-(4x^+xy)=-3x^y+2xy-4x^-xy=-3x^y+xy-4x^所以填上-3x^y+xy-4x^
(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)=-6xy+3x-3y=-6×(-2)+3×1=15
-xy(x³y七次方-3x²y五次方-y)=-xy[(x³y^6)y-3(x²y^4)y-y]=-xy[(xy²)³y-3(xy²
原式=3x-3y-6xy=3-12=-9
这些都忘的差不多了首先把6x^2-6y^2+5xy-4x+7y-2的6x^2-6y^2+5xy化成(2x+3y)(3x-2y),这样就得到(2x+3y)(3x-2y)-4x+7y-2然后把-4x+7y
(3x+2y)(4x-5y)-11(x+y)(x-y)+5xy=12x²-7xy-10y²-11x²+11y²+5xy=x²-2xy+y²=
(4xy+12y)+[7x-(3xy+4y-x)]=4xy+12y+7x-3xy-4y+x=xy+8x+8y=xy+8(x+y)=(-2)+8*3=-2+24=22
(-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*
指数在电脑上实在是难写,我把我写得拍成照片 仅供参考!
xy(x^3y^7-3x^2y^5-5y)x^4y^8-3x^3Y^6-5xy^2=(xy^2)^4-3(xy^2)^3-5xy^2=(-2)^4-3(-2)^3-5(-2)=16+24+10=50
∵x-y=4xy,∴2x+3xy-2yx-2xy-y=2(x-y)+3xyx-y-2xy=8xy+3xy4xy-2xy=112.故答案为:112.
只要结果得-4/3x2y3,即负三分之四乘以x的平方再乘以y的立方.再问:﹙-12x³y⁴﹚÷﹙-3x²y²﹚·﹙-⅓xy﹚=-12÷3×1/3×
[-(x-y)^2/xy]^-4*(y^2-xy/x)^3*(x^4/y^10)÷(xy-y^2/x)^-5=-y(y-x)^29^-x*27^y=3^-2x*3^3y=3^(-2x+3y)=3^(-
(-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