(1) (2m+3)(2m-3)(2) x(x+1)+(2-x)(2+x)(3) (3x-y)(3x+y)+y(x+y)(4) (a+二分之一b)(a-二分之一b)-(3a-2b)(3a+2b)

问题描述:

(1) (2m+3)(2m-3)
(2) x(x+1)+(2-x)(2+x)
(3) (3x-y)(3x+y)+y(x+y)
(4) (a+二分之一b)(a-二分之一b)-(3a-2b)(3a+2b)