【简答题】对函数 ,现有下列命题: ①函数 是偶函数; ②函数 的最小正周期是 ; ③点 是函数 的图象的一个对称中心; ④函数 在区间 上单调递增,在区间 上单调递减. 其中是真命题的是______________________.
【简答题】在函数中,我们把关于x的一次函数 与 称为一对交换函数,如 与 是一对交换函数.称函数 是函数 的交换函数. (1)求函数 y = x +4与交换函数的图像的交点坐标; (2)若函数 y = x + b ( b 为常数)与交换函数的图像及纵轴所围三角形的面积为4,求b 的值.
【单选题】设 是函数 的导函数,有下列命题: ①存在函数 ,使函数 为偶函数; ②存在函数 ,使 的图象相同; ③存在函数 的图象关于x轴对称。 其中真命题的个数为 ( )
【多选题】When we can’t sell a passenger a round-trip ticket, what should we do as the station officers?
A.
The station officer should explain the reason why there’s no round-trip ticket patiently.
B.
The station officer could advise the passenger to buy one-way ticket and get another one-way ticket on the way back.
C.
The station officer could advise the passenger to buy a prepaid transportation card.
D.
The station officer could advise the passenger to download a payment app and pay for the journey conveniently.
【多选题】Do you still remember the third video you watched in Lesson Two this unit? What should the passenger do with the prohibited item?
【简答题】Preferred Products has issued preferred stock with an annual dividend of $8 that will be paid in perpetuity. If the discount rate is 12%, at what price should the stock sell?
【多选题】下列关于会计政策变更的各项表述中,不正确的有
B.
本期发生的交易或者事项与以前相比具有本质差异而采用新的会计政策,不属于会计政策变更
C.
对初次发生的或不重要的交易或者事项采用新的会计政策,属于会计政策变更
【单选题】On May 4, 2005, Joseph Pantera, age 35, completed an application for a life insurance policy on his life and paid the initial annual premium. The coverage under the policy became effective on May 15, ...
【多选题】At an airport, what should the passagers do with the prohibited items?