(a-b)²+3(a-b)-10
=(a-b+5)(a-b-2)
m²/4+mn+n²
=(1/4)(m²+4mn+4n²)
=(1/4)(m+2n)²
2x三次y+8x²y²+8xy三次
=2xy(x²+4xy+4y²)
=2xy(x+2y)²
3x三次-12x²+12x
=3x(x²-4x+4)
=3x(x-2)²
还说我笨明明你最那啥了/w\
看补充……
追答m²/4+mn+n²=(m/2)²+mn+n²=((1/2m)+n)²
2x三次y+8x²y²+8xy三次=2xy(x²+4xy+4y2)=2xy(x+2y)²
3x三次-12x²+12x=3x(x²-4x+4)=3x(x-2)²
看补充……