7x²-63a³-a3a²-3b²y²-9（x+y)²a(x-y)-b(y-x)+c(x-y)x(m+n)-y(n+m)

7x²-63=7(x²-9)=7(x+3)(x-3)
a³-a=a(a-1)(a+1)
3a²-3b²=3(a-b)(a+b)
y²-9（x+y)²=(y-3(x+y))(y+3(x+y))=(-2y-4x)(4y+4x)=-8(y+2x)(y+x)
a(x-y)-b(y-x)+c(x-y)=(x-y)(a+b+c)
x(m+n)-y(n+m)+(m+n)=(m+n)(x-y+1)
(x+y)²-16（x-y)²=(x+y+4(x-y))(x+y-4(x-y))=(5x-3y)(5y-3x)
16-（2a+3b)²=(4-2a-3b)(4+2a+3b)
（x+y+z)²-(x-y-z)²=(x+y+z+x-y-z)(x+y+z-x+y+z)=2x(2y+2z)=4x(y+z)
（x+y)²-14（x+y)+49=(x+y-7)²
a²b²-0.01=(ab-0.1)(ab+0.1)
x²y-2xy²+y³=y(x-y)²
a⁴-8a²b²+16b⁴=(a²-4b²)²=(a-2b)²(a+2b)²
（a²+4）²-16a²=(a²+4-4a)(a²+4+4a)=(a-2)²(a+2)²
x²-xy+1/4y²=(x-1/2y)²
a²x²+16ax+64=(ax+8)²
a²（a-b）²-b²（a+b)²=(a(a-b))²-(b(a+b))²=(a²-ab)²-(ab+b²)²
=(a²-ab+ab+b²)(a²-ab-ab-b²)
=(a²+b²)(-2ab)=-2ab(a²+b²)
2x²+2x+1/2=2(x+1/2)²
（x+1）（x+2）+1/4 =x²+3x+2+1/4=x²+3x+9/4=(x+3/2)²

题太多了，没人有闲心给你详解。

有题号吗,太多了/亲

7(x+3)(x-3)
a(a-1)
3(a+b)(a-b)
(x-y)(a+b+c)
(m+n)(x-y+1)
做了一点，其实挺简单的，太多了，你参考看一下吧，学一下技巧。