Question

为了应用乘法公式计算(x-2y+1)(x+2y-1)，下列变形中正确的是(    )

(A)［x-(2y+1)］²                     (B)［x-(2y-1)］［x+(2y-1)］

(C)［(x-2y)+1］［(x-2y)-1］            (D)［x+(2y-1)］²

Answer 1

B