(2x+3)(y-1)-(x+1)(2y-3); (2a+3b)(2a-3b)(4a^2-9b^2)

问题描述:

(2x+3)(y-1)-(x+1)(2y-3); (2a+3b)(2a-3b)(4a^2-9b^2)

(2x+2+1)(y-1)-(x+1)(2y-2-1)=2(x+1)(y-1)+(y-1)-2(x+1)(y-1)+(x+1)=(y-1)+(x+1)=x+y=(4a²-9b²)(4a²-9b²)=(4a²-9b²)²(我怀疑你题目抄错了,看样子是要你们学习乘方),估计...