①m方(x-y)+n方(y-x)
②(2a-b)方+8ab
③6xy方-9x方y-y三次方
④6p(p+q)-49(p+q)
⑤x五次方-x四次方
⑥3ax方+6axy+3ay方
⑦-3x方+6xy-3y方
⑧a四次方(x-y)+b四次方(y-x)
⑨已知 x方+6x+10+y方-2y=0 求(2x-y)方 的值
①m方(x-y)+n方(y-x)
②(2a-b)方+8ab
③6xy方-9x方y-y三次方
④6p(p+q)-49(p+q)
⑤x五次方-x四次方
⑥3ax方+6axy+3ay方
⑦-3x方+6xy-3y方
⑧a四次方(x-y)+b四次方(y-x)
⑨已知 x方+6x+10+y方-2y=0 求(2x-y)方 的值
m^2(x-y)+n^2(y-x)
=m^2(x-y)-n^2(x-y)
=(m^2-n^2)(x-y)
=(m-n)(m+n)(x-y)
(2a-b)^2+8ab
=4a^2-4ab+b^2+8ab
=4a^2+4ab+b^2
=(2a+b)^2
6xy^2-9x^2y-y^3
=-y(9x^2-6xy+y^2)
=-y(y-3x)^2
6p(p+q)-49(p+q)
=(6p-49)(p+q)
x^5-x^4
=x^4(x-1)
3ax^2+6axy+3ay^2
=3a(x+y)^2
-3x^2+6xy-3y^2
=-3(x^2-2xy+y^2)
=-3(x-y)^2
a^4(x-y)+b^4(y-x)
=(a^4-b^4)(x-y)
=....
x^2+6x+10+y^2-2y=0
x^2+6x+9+y^2-2y+1=0
(x+3)^2+(y-1)^2=0
x=-3 y=1
(2x-y)^2
=(-6-1)^2
=49
1.原式=m(x-y)-n(x-y)
=(m-n)(x-y)
2.原式=4a^2-4ab+b^2+8ab
=(2a+b)^2
3.原式=y(-y^2+6xy-9x^2)
=y[-(y-3x)^2]
=-y(y-3x)^2
4.原式=(6p-49)(p+q)
5.原式=x·x^4-1·x^4
=(x-1)x^4
6.原式=3a(x^2+2xy+y^2)
=3a(x+y)^2
7.原式=-3(x^2-2xy+y^2)
=-3(x-y)^2
8.原式=a^4(x-y)-b^4(x-y)
=(a^4-b^4)(x-y)
9.∵x^2+6x+10+y^2-2y=0
∴x^2+6x+9+y^2-2y+1=0
(x+3)^2+(y-1)^2=0
∴x=-3,y=1
∴2x-y=2x(-3)-1
=-7