> 其他 >
已知x
人气:494 ℃ 时间:2020-06-23 15:59:51
解答
作差得
(x³-1)-(2x²-2x)
=(x-1)(x²+x+1)-2x(x-1)
=(x-1)(x²+x+1-2x)
=(x-1)(x²-x+1)
=(x-1)[(x-1/2)²+3/4]
∵x
推荐
猜你喜欢
© 2024 79432.Com All Rights Reserved.
电脑版|手机版