未知类型:{'options': ['y=2[img=7x15]17e449509cc7c8a.jpg[/img]', ' y=x[img=6x17]17e43604ddc5281.jpg[/img]', ' y=x[img=14x17]17e4363e77b43cf.jpg[/img]', ' y=2+x[img=6x17]17e441974d4175b.jpg[/img]', ' y=-x[img=6x17]17e43604ddc5281.jpg[/img]', ' y=x[img=7x19]17e44950a76b7fc.jpg[/img]'], 'type': 102}
举一反三
- X,Y相互独立,X服从参数为2的泊松分布,Y服从[img=54x25]1803b4181e39f0c.png[/img],则[img=84x25]1803b4182602fd0.png[/img]与[img=86x25]1803b4182e0ab99.png[/img]分别为 A: -1,-7 B: 1, -7 C: 1,17 D: -1, 17
- 求微分方程[img=143x21]17da5f14490e50e.png[/img]的通解,实验命令为(). A: dsolve(D2y-2*Dy+5*y=sin(2*x),x)ans =exp(x)*sin(2*x)*C2+exp(x)*cos(2*x)*C1+1/17*sin(2*x)+4/17*cos(2*x) B: dsolve('D2y-2*Dy+5*y=sin(2*x)','x')ans =cos(2*x)*(sin(4*x)/17 - cos(4*x)/68 + 1/4) - sin(2*x)*(cos(4*x)/17 + sin(4*x)/68) + C1*cos(2*x)*exp(x) - C2*sin(2*x)*exp(x) C: dsolve(D2y-2*Dy+5*y=sin(2*x),'x','y')ans =exp(x)*sin(2*x)*C2+exp(x)*cos(2*x)*C1+1/17*sin(2*x)+4/17*cos(2*x)
- 设随机变量X~t(n)(n>;1),Y=1/X2,则() 未知类型:{'options': ['Y[img=11x9]17e43bbd1cbd80c.jpg[/img]χ[img=6x17]17e43604ddc5281.jpg[/img](n)', ' Y[img=11x9]17e43bbd1cbd80c.jpg[/img]χ[img=6x17]17e43604ddc5281.jpg[/img](n-1)', ' Y~F(n,1)', ' Y~F(1,n)'], 'type': 102}
- 已知随机变量X的分布列如下:[img=386x130]17e43ec4c459e73.png[/img],则E(X)= A: 17/30 B: m未知,无法求出 C: -30/17 D: -17/30
- 下列等值式不正确的是: 未知类型:{'options': ['', '┐([img=10x19]17de6020f4c375c.png[/img]x)A [img=18x11]17de60210176264.png[/img]([img=10x19]17de60210dea9b9.png[/img] x)┐A', '(∃x)(A(x)∧B(x))[img=18x11]17de60210176264.png[/img] (∃x)A(x)∧(∃ x)B(x)', '(∀x)(∀y)(A(x)→B(y))[img=18x11]17de60210176264.png[/img] (∀x)A(x)→(∀y)B(y)'], 'type': 102}
内容
- 0
求不定积分[img=132x48]17da6537fc8dad6.png[/img]; ( ) A: -(4*(cos(x/2)/2 + 2*sin(x/2)))/(17*exp(2*x)) B: (4*(sin(x/2)/2 + 2*sin(x/2)))/(17*exp(2*x)) C: (4*(cos(x/2)/2 + 2*sin(x/2)))/(17*exp(2*x)) D: (4*(cos(x/2)/2 + 2*cos(x/2)))/(17*exp(2*x))
- 1
Whatistheintersectionpointforthegraphsofthelines<em>y</em>=2<em>x</em>+7and<em>y</em>=3<em>x</em>+2? A: (9,25) B: (5,17) C: (-17,-5) D: (17,-7) E: (-7,17)
- 2
一阶公式([img=16x17]17da563f2953679.png[/img]x)(P(x)∨([img=8x14]17da563f348435c.jpg[/img]y)R(y))→Q(x)中量词x的辖域是( ) 未知类型:{'options': ['([img=16x17]17da563f2953679.png[/img]x)(P(x)∨([img=8x14]17da563f348435c.jpg[/img]y)R(y))', ' P(x)', ' (P(x)∨([img=13x16]17da563f4517a67.png[/img]y)R(y))', ' (P(x)∨([img=13x16]17da563f4517a67.png[/img]y)R(y))→Q(x)'], 'type': 102}
- 3
谓词公式([img=14x16]17da56eeb417e47.png[/img]x)P(x,y)∧(([img=8x14]17da6393381999d.jpg[/img]x)Q(x,z)→([img=12x15]17da639354b492d.png[/img]x)([img=8x14]17da6393381999d.jpg[/img]y)R(x,y,z))中量词[img=15x16]17da56ee93ee35a.png[/img]x的辖域是( ) 未知类型:{'options': ['([img=15x16]17da56ee93ee35a.png[/img]x)Q(x,z)→([img=8x14]17da563f348435c.jpg[/img]x)([img=15x16]17da56ee93ee35a.png[/img]y)R(x,y,z))', ' Q(x,z)→([img=15x16]17da56ee93ee35a.png[/img]y)R(x,y,z)', ' Q(x,z)→([img=12x15]17da639354b492d.png[/img]x)([img=8x14]17da6393381999d.jpg[/img]y)R(x,y,z)', ' Q(x,z)'], 'type': 102}
- 4
设随机变量(X,Y)的联合密度函数为f(x,y)=[img=11x33]17e0a705ae7bd6c.jpg[/img]xy,0<;x<;y<;2,则)P(X<;1,Y<;2)= 未知类型:{'options': ['', ' [img=21x34]17e0abc58cd38f8.jpg[/img]', ' [img=18x33]17e0abc597504cc.jpg[/img]', ' [img=11x33]17e0a705ae7bd6c.jpg[/img]'], 'type': 102}