设随机变量X的概率密度为，则X的三阶中心距E（X－EX）3＝（　　）。

A A．只与a有关 B B．只与k有关 C C．与a、k均有关 D D．与a、k均无关

A A．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497246_0_1.png"> B B．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497246_0_2.png"> C C．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497246_0_3.png"> D D．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497246_0_4.png">

A A．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497247_0_2.png"> B B．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497247_0_3.png"> C C．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497247_0_4.png"> D D．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497247_0_5.png">

A A．在x＝1，x＝－1处都连续 B B．在x＝1处连续，x＝－1处不连续 C C．在x＝1，x＝－1处都不连续 D D．在x＝1处不连续，x＝－1处连续

A A．－6，－2 B B．6，－2 C C．－6，2 D D．6，2

A A．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497249_0_2.png"> B B．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497249_0_3.png"> C C．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497249_0_4.png"> D D．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497249_0_5.png">

A A．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497252_0.png"> B B．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497252_0_1.png"> C C．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497252_0_2.png"> D D．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497252_0_3.png">

A A．a＝0或<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497250_0_2.png"> B B．a＝0或<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497250_0_3.png"> C C．b＝1或<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497250_0_4.png"> D D．b＝－1或<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497250_0_5.png">

A A．X＋Y B B．<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20241129/22497253_0.png"> C C．2X D D．X