概率论与数理统计章节测试课后答案2024春

第二章测试

1.设随机变量 具有对称的概率密度函数，即 ，其分布函数为 ，则 （ ）
A: B: C: D:
答案:C
2.设随机变量 ，则随着 增大，概率 的趋势为（ ）
A:保持不变 B:单调增大 C:单调递减 D:增减不定
答案:A
3.设随机变量 的概率密度函数 是偶函数，分布函数为 ,则下列命题正确的是（ ）。
A: .w65519885324s .brush0 { fill: rgb(255,255,255); } .w65519885324s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885324s .font0 { font-size: 348px; font-family: "Times New Roman", serif; } .w65519885324s .font1 { font-style: italic; font-size: 348px; font-family: "Times New Roman", serif; } .w65519885324s .font2 { font-size: 321px; font-family: Symbol, serif; } .w65519885324s .font3 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } ()()1 FxFx +-= B: 为偶函数 C: .w65519885302s .brush0 { fill: rgb(255,255,255); } .w65519885302s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885302s .font0 { font-size: 348px; font-family: "Times New Roman", serif; } .w65519885302s .font1 { font-style: italic; font-size: 348px; font-family: "Times New Roman", serif; } .w65519885302s .font2 { font-size: 321px; font-family: Symbol, serif; } .w65519885302s .font3 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } 2()()1 FxFx --= D: 为奇函数
答案:A
4.设 .w65519885283s .brush0 { fill: rgb(255,255,255); } .w65519885283s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885283s .font0 { font-size: 227px; font-family: "Times New Roman", serif; } .w65519885283s .font1 { font-size: 348px; font-family: "Times New Roman", serif; } .w65519885283s .font2 { font-style: italic; font-size: 348px; font-family: "Times New Roman", serif; } .w65519885283s .font3 { font-style: italic; font-size: 321px; font-family: Symbol, serif; } .w65519885283s .font4 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } 22 ~(,4),~(,5) XNYN mm ,若 .w65519885266s .brush0 { fill: rgb(255,255,255); } .w65519885266s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885266s .font0 { font-size: 348px; font-family: "Times New Roman", serif; } .w65519885266s .font1 { font-style: italic; font-size: 348px; font-family: "Times New Roman", serif; } .w65519885266s .font2 { font-style: italic; font-size: 321px; font-family: Symbol, serif; } .w65519885266s .font3 { font-size: 321px; font-family: Symbol, serif; } .w65519885266s .font4 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } (4),(5) pPXqPY mm =£-=³+ ，则下列不正确的有（ ）。
A:对任意实数 .w65519885247s .brush0 { fill: rgb(255,255,255); } .w65519885247s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885247s .font0 { font-style: italic; font-size: 321px; font-family: Symbol, serif; } .w65519885247s .font1 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } m 都有 .w65519885227s .brush0 { fill: rgb(255,255,255); } .w65519885227s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885227s .font0 { font-style: italic; font-size: 348px; font-family: "Times New Roman", serif; } .w65519885227s .font1 { font-size: 321px; font-family: Symbol, serif; } .w65519885227s .font2 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } pq = B:对个别 .w65519885240s .brush0 { fill: rgb(255,255,255); } .w65519885240s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885240s .font0 { font-style: italic; font-size: 321px; font-family: Symbol, serif; } .w65519885240s .font1 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } m ，才有 .w65519885221s .brush0 { fill: rgb(255,255,255); } .w65519885221s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885221s .font0 { font-style: italic; font-size: 348px; font-family: "Times New Roman", serif; } .w65519885221s .font1 { font-size: 321px; font-family: Symbol, serif; } .w65519885221s .font2 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } pq = C:对任意实数 .w65519885203s .brush0 { fill: rgb(255,255,255); } .w65519885203s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885203s .font0 { font-style: italic; font-size: 321px; font-family: Symbol, serif; } .w65519885203s .font1 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } m 都有 .w65519885181s .brush0 { fill: rgb(255,255,255); } .w65519885181s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885181s .font0 { font-style: italic; font-size: 348px; font-family: "Times New Roman", serif; } .w65519885181s .font1 { font-size: 321px; font-family: Symbol, serif; } .w65519885181s .font2 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } pq " x="345" y="224"> > D:对任意实数 .w65519885209s .brush0 { fill: rgb(255,255,255); } .w65519885209s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885209s .font0 { font-style: italic; font-size: 321px; font-family: Symbol, serif; } .w65519885209s .font1 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } m 都有 .w65519885188s .brush0 { fill: rgb(255,255,255); } .w65519885188s .pen0 { stroke: rgb(0,0,0); stroke-width: 1; stroke-linejoin: round; } .w65519885188s .font0 { font-style: italic; font-size: 348px; font-family: "Times New Roman", serif; } .w65519885188s .font1 { font-size: 321px; font-family: Symbol, serif; } .w65519885188s .font2 { font-weight: bold; font-size: 76px; font-family: System, sans-serif; } pq <
答案:BCD
5.连续型随机变量X的概率密度函数f(x)也一定是连续函数。（ ）
A:错 B:对
答案:A