以下哪一个矩阵是对称矩阵（ ）A.[img=52x49]180323c14a206df.png[/img]；B.[img=81x76]180323c1566722a.png[/img]；C.[img=81x76]180323c1618fc97.png[/img]；D.[img=53x49]180323c169aaa71.png[/img]
A: [img=52x49]180323c1722d68a.png[/img]
B: [img=81x76]180323c17d00cab.png[/img]
C: [img=81x76]180323c1871372a.png[/img]
D: [img=53x49]180323c18f20943.png[/img]
E: [img=81x76]180323c17d00cab.png[/img]
F: [img=81x76]180323c1871372a.png[/img]
A: [img=52x49]180323c1722d68a.png[/img]
B: [img=81x76]180323c17d00cab.png[/img]
C: [img=81x76]180323c1871372a.png[/img]
D: [img=53x49]180323c18f20943.png[/img]
E: [img=81x76]180323c17d00cab.png[/img]
F: [img=81x76]180323c1871372a.png[/img]
举一反三
- 设3阶矩阵[img=17x18]17e0be09b818287.png[/img]有特征值为[img=129x25]17e0be09c3a0260.png[/img]，其对应的特征向量分别为[img=71x25]17e0be09cfc7e66.png[/img]，设[img=109x25]17e0be09db9ab38.png[/img]，则[img=60x20]17e0be09e7114f0.png[/img]（）。 未知类型：{'options': ['', ' [img=81x76]17e0be09ff26365.png[/img]', ' [img=81x76]17e0be0a0abb7c4.png[/img]', ' [img=81x76]17e0be0a1719504.png[/img]'], 'type': 102}
- 令F(x):x是有理数,G(x):x是实数。将命题“所有的有理数都是实数,但有的有实数不是有理数”符号化为() 未知类型：{'options': ['17e0a83a4157352.jpgx(F(x)∧G(x))∧[img=8x14]17e0a83a35505d4.jpg[/img]x(G(x)[img=14x9]17e0a73094b5dcf.jpg[/img][img=10x11]17e0a839b915354.jpg[/img]F(x))', ' [img=8x14]17e0a83a4157352.jpg[/img]x(F(x)[img=14x9]17e0a73094b5dcf.jpg[/img]G(x))∧[img=8x14]17e0a83a35505d4.jpg[/img]x(G(x)∧[img=10x11]17e0a839b915354.jpg[/img]F(x))', ' [img=8x14]17e0a83a4157352.jpg[/img]x(F(x)∧G(x))∧[img=8x14]17e0a83a35505d4.jpg[/img]x(G(x)∧[img=10x11]17e0a839b915354.jpg[/img]F(x))', ' [img=8x14]17e0a83a4157352.jpg[/img]x(F(x)[img=14x9]17e0a73094b5dcf.jpg[/img]G(x))∧[img=8x14]17e0a83a35505d4.jpg[/img]x(G(x)[img=14x9]17e0a73094b5dcf.jpg[/img][img=10x11]17e0a839b915354.jpg[/img]F(x))'], 'type': 102}
- 设随机变量X的概率密度[img=190x71]17de89917dd344e.png[/img]，则[img=87x47]17de89918b2d7b8.png[/img]的值为 A: 5 B: 3 C: 81/16 D: 4
- Which one of the following strokes is not a basic one? A: [img=84x79]18039c7fcdb211d.jpg[/img] B: [img=81x76]18039c7fd5c3c21.jpg[/img] C: [img=32x84]18039c7fde89790.jpg[/img] D: [img=64x71]18039c7fe762b3f.jpg[/img]
- X~N(1,1), 密度函数为[img=37x25]18038fe689205b5.png[/img], 分布函数为F(x), 则（ ） A: [img=198x25]18038fe690a03ee.png[/img] B: [img=101x25]18038fe69af96aa.png[/img] C: [img=67x25]18038fe6a3b8e5b.png[/img][img=118x25]18038fe6ab93d6f.png[/img] D: F(x)=F(-x)