qiuliling
幼苗
共回答了23个问题采纳率:91.3% 举报
1.4a²-4(ab+4)+b²
=4a²-4ab+b²-16
=(2a-b)²-16
=(2a-b+4)(2a-b-4)
2.a的四次方-x²+4ax-4a²
=a^4-(x²-4ax+4a²)
=a^4-(x-2a)²
=(a²+x-2a)(a²-x+2a)
3.a²b²c-ab³c+a²bc²-ab²c²
=abc(ab-b²+ac-bc)
=abc[b(a-b)+c(a-b)]
=abc(b+c)(a-b)
4.9m²-6m+2n-n²
=(9m²-6m+1)-(n²-2n+1)
=(3m-1)²-(n-1)²
=(3m+n-2)(3m-n)
5.xy-xz-y²+2yz-z²
=x(y-z)-(y²-2yz+z²)
=x(y-z)-(y-z)²
=(y-z)(x-y+z)
1年前
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