判断题:下列式子中对的请打勾,错的在括号内更正.

题目

判断题:下列式子中对的请打勾,错的在括号内更正.
1.(2a-b)^2=4a^2-2ab+b^2( )
2.(m+n)(n^2-mn+m^2)=m^3+n^3( )
3.(1-x)(x-1)=1-x^2( )
4.(2-a)(a+2)=2-a^2( )
5.x^3+8y^3=(x+2y)(x^2-2xy+y^2)( )
6.(1/3a-3/2b)^2=1/9a^2-ab+9/4b^2( )

答案

1.(2a-b)^2=4a^2-2ab+b^2( 4a^2-4ab+b^2 )
2.(m+n)(n^2-mn+m^2)=m^3+n^3( 对 )
3.(1-x)(x-1)=1-x^2( -x^2+2x-1 )
4.(2-a)(a+2)=2-a^2( 4-a^2 )
5.x^3+8y^3=(x+2y)(x^2-2xy+y^2)( 对 )
6.(1/3a-3/2b)^2=1/9a^2-ab+9/4b^2( 对 )