The function [img=118x45]1803e256879b359.png[/img] is an even function, where [img=43x19]1803e2568fe9357.png[/img] and [img=43x23]1803e25698e34e9.png[/img].
举一反三
- 设投掷1颗骰子的点数为X,则( ) 未知类型：{'options': ['E(X)=3.5,D(X)= [img=29x21]17e43c3db9dc21b.png[/img]', ' E(X)=3.5, D(X)= [img=22x41]17e43c3dc2146ee.png[/img]', ' E(X)=3.5,D(X)=3.5', ' E(X)=3.5,D(X)=[img=22x41]17e43c3dcacf7d1.png[/img]'], 'type': 102}
- 设X为随机变量，若数学期望E(X)存在，则数学期望E(E(X))=__________。 A: E(X) B: 0 C: [img=51x27]18038f919d83a08.png[/img] D: [img=63x27]18038f91a6f0476.png[/img]
- If [img=34x25]1803e254fa72e37.png[/img] is an even function and [img=33x25]1803e25502f5f78.png[/img] is an odd function，then ( ). A: All [img=191x25]1803e2550bd75da.png[/img] are even functions; B: All [img=191x25]1803e25513d5400.png[/img] are odd functions; C: [img=124x25]1803e2551c3ff9f.png[/img]are odd functions and [img=56x25]1803e25523e8c1c.png[/img]is an even function; D: [img=124x25]1803e2552c8c3c6.png[/img] are even functions and [img=56x25]1803e25534c2a44.png[/img] is an odd function.
- 设随机变量 X ~ e([img=11x19]1803bbe33f2dc36.png[/img])，则 D(X )= [img=18x43]1803bbe34777894.png[/img].
- 设随机变量[img=15x19]1803c5fbd2ccac8.png[/img]的期望E(X)=2，方差D(X)=4，随机变量[img=11x19]1803c5fbdae292b.png[/img]的期望E(Y)=4，方差D(Y)=9,E(XY)=10,则[img=33x23]1803c5fbe3431f2.png[/img]的相关系数[img=43x43]1803c5fbeab6ece.png[/img]。( )