举一反三
- True or False : If [img=52x32]1802ddd740eab2f.png[/img] does not exist and [img=51x32]1802ddd748fbd7e.png[/img] does not exist either, then [img=94x33]1802ddd750d8d30.png[/img] does not exist. A: True. B: False. C: - D: -
- 若[img=67x35]1802dbd0ad6fa0c.png[/img]存在，[img=67x35]1802dbd0b5f8a34.png[/img]不存在，则[img=134x35]1802dbd0be79aab.png[/img]一定不存在.
- 若[img=67x35]1802cdb7afe2fac.png[/img]存在，[img=67x35]1802cdb7b80fada.png[/img]不存在，则[img=134x35]1802cdb7c449ed0.png[/img]一定不存在.
- 若[img=67x35]18038487f9f1919.png[/img]存在，[img=67x35]180384880219f22.png[/img]不存在，则[img=134x35]1803848809fd232.png[/img]一定不存在.
- 若[img=67x35]1802cdc0c36f830.png[/img]存在，[img=67x35]1802cdc0cc8c612.png[/img]不存在，则[img=134x35]1802cdc0d476b97.png[/img]一定不存在.
内容
- 0
若[img=67x35]1802dc55801a6cd.png[/img]存在，[img=67x35]1802dc5589058fe.png[/img]不存在，则[img=134x35]1802dc55918336e.png[/img]一定不存在.
- 1
3. Let [img=161x53]1802dde8d59661c.png[/img] and [img=180x61]1802dde8df7d956.png[/img].Determine whether [img=62x33]1802dde8e7e5fb9.png[/img] and [img=61x33]1802dde8f088425.png[/img] exist or not. A: (A) [img=62x33]1802dde8f81f6da.png[/img] and [img=61x33]1802dde8ff2f966.png[/img] both exist. B: (B) [img=62x33]1802dde8f81f6da.png[/img] exists but [img=61x33]1802dde8ff2f966.png[/img] does not exist. C: (C) [img=62x33]1802dde8f81f6da.png[/img] does not exist but [img=61x33]1802dde8ff2f966.png[/img] exists. D: (D) [img=62x33]1802dde8f81f6da.png[/img] and [img=61x33]1802dde8ff2f966.png[/img] do not exist.
- 2
设f(x)在[a, b]上连续., 则[img=67x35]17e0a6a122259e5.png[/img]=( ) 未知类型：{'options': ['', ' [img=111x35]17e0ac6d2043082.png[/img]', ' [img=112x35]17e0ac6d2965cd1.png[/img]', ' [img=111x35]17e0ac6d3381889.png[/img]'], 'type': 102}
- 3
如果[img=75x36]1802e078cdd4522.png[/img]与[img=75x36]1802e078d5ae470.png[/img]存在，则（ ） A: [img=67x35]1802e078dd737a1.png[/img]存在且[img=130x35]1802e078e6530e4.png[/img]; B: [img=67x35]1802e078dd737a1.png[/img]存在但不一定有[img=130x35]1802e078e6530e4.png[/img]; C: [img=67x35]1802e078dd737a1.png[/img]不一定存在; D: [img=67x35]1802e078dd737a1.png[/img]一定不存在.
- 4
设随机变量X服从均值为2的指数分布，X的分布函数为F(x)，数学期望为E(X)，方差为D(X)，则以下结果正确的是 A: [img=128x28]1802d3b369ab5fe.png[/img] B: D(X)=4 C: P(X<2︱X>1)=F(1) D: P(X>2︱X>1)= F(1) E: [img=112x27]1802d3b372fb534.png[/img] F: D(X)=E(X) G: P(X≤2︱X>1)= F(2) H: [img=82x27]1802d3b37bbbf05.png[/img]