[初一数学整式乘法与因式分解题目](2x+1)(-2x+1) =(1+2x)(1-2x) =1-4x^2 10.5x9.5 =(10+0.5)(10-0.5) =100-0.5^2 =100-0.25 =99.75 (x-2y) (x+2y)-(x+2y)² =(x+2y)(x-2y-(x+2y)) =(x+2y)(x-2y-x-2y) =-4y(x...+阅读
-(2x-1)^3+x^3
= -{(2x-1)^3-x^3}
= -{(2x-1)-x}{(2x-1)^2+x(2x-1)+x²}
= -(x-1)(7x²-6x+1)
64-x^2y^2-(x^2+16y^2)
(有没有抄错?)
1-(x^2-2xy+y^2)
= 1-(x-y)²
= (1+x-y)(1-x+y)
x^3+3x^2+3x+2
= x^3-1+3x^2+3x+3
= (x-1)(x^2+x+1)+3((x^2+x+1)
= (x^2+x+1)(x-1+3)
= (x^2+x+1)(x+2)
2a^2b(a-b)+ab(b-a)^2+2ab^2(b-a)
= 2a^2b(a-b)+ab(a-b)^2-2ab^2(a-b)
= ab(a-b){2a+(a-b)-2b)}
= ab(a-b)(3a-3b)
= 3ab(a-b)²
25x^2y(m-2n)^2-10xy^2(2n-m)^3
= 25x^2y(m-2n)^2+10xy^2(m-2n)^3
= 5xy(m-2n)²(4x+2y)
以下为关联文档:
数学的初二整式的乘除与因式分解题解(1)由题意得 (m+4+n+4)(m+4-n-4)=16 即(m+n+8)(m-n)=16 8(m-n)=16 m-n=2 所以m=1 n=-1 所以 m²+n²-(m/n) =1²+(-1)² - 1/(-1) =3 (2) ah/2=(a+4)(h-4)/2 ah = ah-4a+4h-16 4(a...
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