(x-y)的立方等于-(x-y)的立方吗
(x-y)的立方等于-(x-y)的立方吗
日期:2021-04-18 11:28:13 人气:1
不等于。
(x-y)³=x³-3x²y+3xy²-y³,
-(x-y)³=-(x³-3x²y+3xy²-y³)=-x³+3x²y-3xy²+y³
(x-y)³=x³-3x²y+3xy²-y³,
-(x-y)³=-(x³-3x²y+3xy²-y³)=-x³+3x²y-3xy²+y³
(x-y)的立方等于-(x-y)的立方吗