题目

(8a^3b-5a^2b^2)/4ab怎么做?
还有(x+2y-3)(x-2y+3)
[(x-2y)^2+(x-2y)(2y+x)-2x(2x-y)]/2x共三道题,

提问时间：2020-10-09

答案

(8a^3b-5a^2b^2)/4ab
=8a^3b/4ab-5a^2b^2/4ab
=2a^2-5ab/4

(x+2y-3)(x-2y+3)
=[x+(2y-3)]*[x-(2y-3)]
=x^2-(2y-3)^2
=x^2-4y^2+12y-9

[(x-2y)^2+(x-2y)(2y+x)-2x(2x-y)]/2x
=[x^2-4xy+4y^2+x^2-4y^2-4x^2+2xy]/2x
=[-2x^2-2xy]/2x
=-x-y