急 x^3-3x^2+6xy-12y^2+8y^3x^2-2xy+y^2-2x+2y+1a^2(a+1)-b^2(b+1)(a-4)^2+(b-4)^2+2(ab-8)(x^2+x+1)(x^2+x+2)-6当x-y=1时,求x^4-xy^3-x^3y-3x^2y+3xy^2+y^4的值有些用分组分解法(写分组过程),有些用十字相乘法._百度作业帮
急 x^3-3x^2+6xy-12y^2+8y^3x^2-2xy+y^2-2x+2y+1a^2(a+1)-b^2(b+1)(a-4)^2+(b-4)^2+2(ab-8)(x^2+x+1)(x^2+x+2)-6当x-y=1时,求x^4-xy^3-x^3y-3x^2y+3xy^2+y^4的值有些用分组分解法(写分组过程),有些用十字相乘法.
急 x^3-3x^2+6xy-12y^2+8y^3x^2-2xy+y^2-2x+2y+1a^2(a+1)-b^2(b+1)(a-4)^2+(b-4)^2+2(ab-8)(x^2+x+1)(x^2+x+2)-6当x-y=1时,求x^4-xy^3-x^3y-3x^2y+3xy^2+y^4的值有些用分组分解法(写分组过程),有些用十字相乘法.
x^3-3x^2+6xy-12y^2+8y^3=(x+2y)(x^2-2xy+4y^2)-3(x^2-2xy+4y^2)=(x^2-2xy+4y^2)(x+2y-3)x^2-2xy+y^2-2x+2y+1=(x-y)^2-2(x-y)+1=(x-y-1)^2a^2(a+1)-b^2(b+1)=a^3-b^3+(a^2-b^2)=(a-b)(a^2+ab+b^2+a+b)(a-4)^2+(b-4)^2+2(ab-8)=a^2+b^2+2ab-8(a+b)+16=(a+b-4)^2(x^2+x+1)(x^2+x+2)-6=(x^2+x+1)^2+(x^2+x+1)-6=(x^2+x+4)(x^2+x-1)当x-y=1时,x^4-xy^3-x^3y-3x^2y+3xy^2+y^4=(x^4+y^4-2x^2y^2)-(xy^3+x^3y-2x^2y^2)-3xy(x-y)=(x+y)^2-xy-3xy=(x-y)^2=1先化简 再求值 [(3x+2y)(2x-3y)-6(x+y)(x-y)]^3/2xy^2 其中 x先化简 再求值 [(3x+2y)(2x-3y)-6(x+y)(x-y)]^3/2xy^2 其中 x=-2/5 y=1/2_百度作业帮
先化简 再求值 [(3x+2y)(2x-3y)-6(x+y)(x-y)]^3/2xy^2 其中 x先化简 再求值 [(3x+2y)(2x-3y)-6(x+y)(x-y)]^3/2xy^2 其中 x=-2/5 y=1/2
先化简 再求值 [(3x+2y)(2x-3y)-6(x+y)(x-y)]^3/2xy^2 其中 x先化简&再求值&[(3x+2y)(2x-3y)-6(x+y)(x-y)]^3/2xy^2&其中&x=-2/5&y=1/2
先拆小括号（6x∧2-5xy-6y∧2-6x∧2+6y∧2）于是括号内等于-5xy拆开后等于-125x∧3y∧3÷2xy∧2等于-125/2x∧2y
把xy的值带进去代进去，结果是-5
[(3x+2y)(2x-3y)-6(x+y)(x-y)]³/(2xy²)=[(6x²-5xy-6y²)-6(x²-y²)]³/(2xy²)=(6x²-5xy-6y²-6x²+6y²)³/(2xy²)=(-5xy)³/(2...几道数学初一下的填空题1.1/2xy^2·(-4x^3·y)=2.(2x^3y)^2·(-3x^2y^3z)=3.(4a^2)^3·(-2a^3)^2=4.(-2x^3y)(3xy^2-3xy+1)=5.(n+4)(n-2)=6.(2m-3n)(3m-5n)=_百度作业帮
几道数学初一下的填空题1.1/2xy^2·(-4x^3·y)=2.(2x^3y)^2·(-3x^2y^3z)=3.(4a^2)^3·(-2a^3)^2=4.(-2x^3y)(3xy^2-3xy+1)=5.(n+4)(n-2)=6.(2m-3n)(3m-5n)=
几道数学初一下的填空题1.1/2xy^2·(-4x^3·y)=2.(2x^3y)^2·(-3x^2y^3z)=3.(4a^2)^3·(-2a^3)^2=4.(-2x^3y)(3xy^2-3xy+1)=5.(n+4)(n-2)=6.(2m-3n)(3m-5n)=
1.1/2xy^2·(-4x^3·y)= -2x^4y^32.(2x^3y)^2·(-3x^2y^3z)= -12x^8y^5z3.(4a^2)^3·(-2a^3)^2= 256a^124.(-2x^3y)(3xy^2-3xy+1)= -6x^4y^3+6x^4y^2-2X63y5.(n+4)(n-2)= n^2+2n-86.(2m-3n)(3m-5n)=6n^2-19mn+15n^2
1-2x^4y^32、-12x^8y^5z3
-6x^4y^3+6x^4y^2-2x^3y5
6m^2-19mn+15n^2几道计算题,快.计算：（-2a)^2/a=(9x^4-6x^3)/3x^2=(1.8*10^12)/(6*10^5)=分解因式：2x^2-12x+18=化简：a-b/a^2-b^2=约分：x^2+2x-3/9-x^2=需过程：化简求值：2x^3+4x-1/3x^2-(x+3x^2-2x^3),其中x=-3计算：（6x^3y^2)^2*(-1/3xy^2)_百度作业帮
几道计算题,快.计算：（-2a)^2/a=(9x^4-6x^3)/3x^2=(1.8*10^12)/(6*10^5)=分解因式：2x^2-12x+18=化简：a-b/a^2-b^2=约分：x^2+2x-3/9-x^2=需过程：化简求值：2x^3+4x-1/3x^2-(x+3x^2-2x^3),其中x=-3计算：（6x^3y^2)^2*(-1/3xy^2)
几道计算题,快.计算：（-2a)^2/a=(9x^4-6x^3)/3x^2=(1.8*10^12)/(6*10^5)=分解因式：2x^2-12x+18=化简：a-b/a^2-b^2=约分：x^2+2x-3/9-x^2=需过程：化简求值：2x^3+4x-1/3x^2-(x+3x^2-2x^3),其中x=-3计算：（6x^3y^2)^2*(-1/3xy^2)^3/(8/3x^7y^10)计算：(a-b)^3*(-a+b)^2/(b-a)^4计算：（2x^3y^3-6x^2y+4xy^2)/[(-2x)*(-y)]化简：a^2+ab-2b^2/a^2+2ab+2b+a
x^2-3x+2/x^2-6x+5不改变分式的值,把下列各式的分子与分母各项系数化为整数0.5x-0.07y/3x+2y(a+1/4b)/(3/4a-2b)
计算：（-2a)^2/a= 4a(9x^4-6x^3)/3x^2= 3x^2 - 2x(1.8*10^12)/(6*10^5)= 3 * 10^6分解因式：2x^2-12x+18= 2 (x-3)^2 化简：a-b/a^2-b^2= 1/(a+b) 约分：x^2+2x-3/9-x^2= (x-1)/(3-x)化简求值：2x^3+4x-1/3x^2-(x+3x^2-2x^3),其中x=-34x^3+3x-3x^2-1/3x^2 = x (4x^2-3x+3)-1/3x^2 = (-3)*(36+9+3)-1/27 =- 144 - 1/27 计算：（6x^3y^2)^2*(-1/3xy^2)^3/(8/3x^7y^10) = (36x^6y^4) * (3x^7y^10)/ [8 * (27x^3y^6)]= (4 * 9 * 3 * x^13 * y^14)/( 8 * 27 * 3x^3y^6)= x^10y^8/2计算：(a-b)^3*(-a+b)^2/(b-a)^4= (a-b)^3 * (a-b)^2 / (a-b)^4= (a-b) 计算：（2x^3y^3-6x^2y+4xy^2)/[(-2x)*(-y)] = 2xy * (x^2y^2-3x+2y)/(2xy)= x^2y^2-3x+2y化简：a^2+ab-2b^2/a^2+2ab+2b+a = [(a-b)(a+2b)]/[(a+1)(a+2b)] = (a-b)/ (a+1) x^2-3x+2/x^2-6x+5= [(x-1)(x-2)]/[(x-1)(x-5)]=(x-2)/(x-5) 不改变分式的值,把下列各式的分子与分母各项系数化为整数 0.5x-0.07y/3x+2y = x/2 - 7y/300x +2y(a+1/4b)/(3/4a-2b) = (4a+b)/(3a-8b)解2x^2+4xy-2x-y+2=0,3x^2+6xy-x+3y=0 的方程组_百度作业帮
解2x^2+4xy-2x-y+2=0,3x^2+6xy-x+3y=0 的方程组
解2x^2+4xy-2x-y+2=0,3x^2+6xy-x+3y=0 的方程组
2x^2+4xy-2x-y+2=0-------------13x^2+6xy-x+3y=0--------2由1可得：2x（x+2y-1）-y+2 =0------3由2可得：3x（x+2y-1)+2x+3y=0-------4由4-3得：x（x+2y-1)+2x+4y-2=0------5由5得：（x+2y-1)（x+2）=0所以：x+2y-1=0或（x+2）=0解得：x=-2,y=14/9将x=1-2y代入1式中得：y=2,又因为x=1-2y所以x=-3解得x=-3,y=2.综上：该组二元二次方程解集{（x,y）|(-3,2),(-2,14/9)}}