（1）.16 x3-24 x2 y2+12x y4-2 y6 2(2x-y2)3（2）.a3+3a2 b+3b2 a-7b3（a-b）(a2+4ab+7b2)（3）.x2-x-(y-3)(y-4)(x-y+3)(x+y-4)(4).x4+y4+(x+y)42(x2+xy+y2)2另加5-15分!

来源：学生作业帮助网编辑：作业帮时间：2024/11/17 13:25:25

（1）.16 x3-24 x2 y2+12x y4-2 y6 2(2x-y2)3（2）.a3+3a2 b+3b2 a-7b3（a-b）(a2+4ab+7b2)（3）.x2-x-(y-3)(y-4)(x-y+3)(x+y-4)(4).x4+y4+(x+y)42(x2+xy+y2)2另加5-15分!
（1）.16 x3-24 x2 y2+12x y4-2 y6
2(2x-y2)3
（2）.a3+3a2 b+3b2 a-7b3
（a-b）(a2+4ab+7b2)
（3）.x2-x-(y-3)(y-4)
(x-y+3)(x+y-4)
(4).x4+y4+(x+y)4
2(x2+xy+y2)2
另加5-15分!

（1）.16 x3-24 x2 y2+12x y4-2 y6 2(2x-y2)3（2）.a3+3a2 b+3b2 a-7b3（a-b）(a2+4ab+7b2)（3）.x2-x-(y-3)(y-4)(x-y+3)(x+y-4)(4).x4+y4+(x+y)42(x2+xy+y2)2另加5-15分!
（1）.16 x3-24 x2 y2+12x y4-2 y6
=2(8x^3-12x^y^2+6xy^4-y^6)
=2
=2(2x-y^2)(4x^2-4xy^2+y^4)
=2(2x-y2)3
（2）.a3+3a2 b+3b2 a-7b3
=(a^3-a^2b)+(4a^2b-4b^3)+(3b^2a-3b^3)
=（a-b）a^2+（a-b）（4ab+4b^2)+（a-b）3b^2
=（a-b）(a^2+4ab+7b^2)
（3）.x2-x-(y-3)(y-4)
=x^2-x-y^2+7y-12
= x^2-y^2-x+7y-12
=(x+y)(x-y)-(x-7y)-12（用十字相乘法）
=(x-y+3)(x+y-4)
(4).x4+y4+(x+y)4
=x^4+y^4+x^4+4x^3y+6x^2y^2+4xy^3+y^4
=2(x^4+2x^3y+3x^2y^2+2xy^3+y^4)
=2
=2
=2(x^2+xy+y^2) (x^2+xy+y^2)
=2(x^2+xy+y^2)^2
打字打得好累啊.

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1.16x^3－24x^2y^2+12xy^4－2y^6
=2(8x^3－y^6)－12xy^2(2x－y^2)
=2(2x－y^2)(4x^2+2xy^2+y^4)－12xy^2(2x－y^2)
=2(2x－y^2)(4x^2－4xy^2+y^4)
=2(2x－y^2)^3
2.a^3+3a^2b+3b^2a－7b^3
=a^3+3a^2b+3b^2a+b^3－8b^3
=(a+b)^3－8b^3
=(a+b－2b)[(a+b)^2+2b(a+b)+4b^2]
(a－b)(a^2+4ab+7b^2)
2.x^2－x－(y－3)(y－4)
=x^2－y^2－x+7y－12
=(x+y)(x－y)－4(x－y)+3(x+y)－12
=(x+y－4)(x－y)+3(x+y－4)
=(x+y－4)(x－y+3)
4.x^4+y^4+(x+y)^4
=2x^4+4xy^3+6x^2y^2+4x^3y+2y^4
=2x(x^3－y^3)+6xy(y^2+xy+x^2)－2y(x^3－y^3)
=2(x－y)(x－y)(x^2+xy+y^2)+6xy(y^2+xy+x^2)
=2(x^2+xy+y^2)(x^2－2xy+y^2+3xy)
=2(x^2+xy+y^2)^2

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因式分解：x3+（y-1）x2-2xy-y2 若x1/y1 =x2/y2 =x3/y3 =1/2,则（x1+x2-x3)/（y1+y2-y3）=? matlab如何将一组数代入原方程的字母里?syms x1 x2 x3 x4 y1 y2 y3 y4 X1 X2 X3 X4 Y1 Y2 Y3 Y4A=[x1,y1,1,0,0,0,-x1*X1,-y1*X1;0,0,0,x1,y1,1,-x1*Y1,-y1*Y1;x2,y2,1,0,0,0,...-x2*X2,-y2*X2;0,0,0,x2,y2,1,-x2*Y2,-y2*Y2;x3,y3,1,0,0,0,-x3*X3,-y3*X3; （1）.16 x3-24 x2 y2+12x y4-2 y6 2(2x-y2)3（2）.a3+3a2 b+3b2 a-7b3（a-b）(a2+4ab+7b2)（3）.x2-x-(y-3)(y-4)(x-y+3)(x+y-4)(4).x4+y4+(x+y)42(x2+xy+y2)2另加5-15分! MATLAB 已知3点求夹角>> x1=1;y1=1;x2=0;y2=0;x3=0;y3=3;theta=acosd(dot([x1-x2,y1-y2],[x3-x2,y3-y2])/(norm([x1-x2,y1-y2])*norm([x1-x2,y3-y2])))theta =47.8696>> x1=1;y1=1;x2=0;y2=0;x3=0;y3=3;theta=acos(dot([x1-x2,y1-y2],[x3-x2,y3-y2])/(norm([x1-x2, y3-y2-y+1/y2-1 × x2-1/x3-x2-x+1 × x-1/y-1化简为什么重心坐标为x1+x2+x3)/3,(y1+y2+y3)/3令A(x1,y1)B(x2,y2)C(x3,y3) BC中点是((x2+x3)/2,(y2+y3)/2),然后不是和坐标向加后再乘1/3吗? 已知反比例函数y=k/x（k>0）图像上三点分别是（x1,y1）、（x2,y2）、（x3,y3）,且x1=-2,x2=-1x3=1,试判断y1、y2、y3的大小关系在反比例y=-1/x的图像中,有三点（x1,y1),(x2,y2),(x3.y3),若x1>x2>0>x3,y1,y2,y3,的关系求方程x3+x2y+xy2+y3=8（x2+xy+y2+1）的全部整数解因式分解：x2-y2+x3-y3 X2/X1(X1+X2)+X3/(X1+X2)(X1+X2+X3)+.Xn/（x1+x2+...Xn-1)(X1+X2...+Xn） (x-y)2(x2+xy+y2)2-(x3+y3)(-x3+y3),其中x=1,y=-1 已知x>0,y>0 x3－y3＝x2－y2,求证 1 设x>0,y>0,x2-y2=x3-y3.求证：1 已知x>0,y>0 x3－y3＝x2－y2,求证 1 已知x+y=1,x3+y3=100.求x2+y2的值若x+y=1,x2+y2=3,那么x3+y3的值