• 2022-10-26
    设[tex=6.714x2.786]WJjqTt+wsb5RrYXOGySYf8IP/i2NWtGNvoUiJ7+98izTb1rpyi4HhmSHV5uQ55SeWn0/eoafGZJrL85BWrmbeg==[/tex]已知[tex=3.857x1.429]EG5u+OowecLEM2uk1RK3kEPEcoRCcybQdTnAplTnuQM=[/tex]存在,求 [tex=1.857x1.214]Y70jMLhXTZtWBpbjkUWtww==[/tex].
  • 解 设[tex=9.214x2.786]P/Quq103RqbAtoN+TeDnZBZJdORrG5ub+k3+FULSyw/fp980dHKeLx8NhEC651E3kIrKAULb1tDb8QkIHEDXE2JED828m72XqhfGSYwfJgegL7Uqv62GpeFif8Q7825V[/tex],则[tex=26.571x2.786]075gCzZzsMRb6HYXYk9X95BT8z7z4e+4OInb7Y8WX7n3c0Vq+hKs74rWriYwYnr3/dTPWFNCf41e6QyxPrLJ2p/7oMq6Q9JexGCb6uyDjUyAiKxNVo7O91ZuCWIqxqVMDkbb46ewzd1SfwZO4hOCG4h2f/H1v5VdltSM8w9UUIboACovOV5OjCdWThUSozL5UI/haVMyydQLnqFRvmtWQBctZUal82EqygVy9Y+8UcWYJJ6l6onavCicE+UqNK5W28fU/TKg65haTQBpR9NMM6b7XkZ0wd6L2J1AE4Ph9wX7gTS6bnYV/FUA5l1hnUaf4gWjDbl0u1ILqbqnGTVt3gfs5IlgJWudSdOtCIr3DTw7xwii76K2lLcc53ZsQEgq[/tex]因此[tex=8.714x1.214]FFitFABrm24sNpVNj8PgE4JMhWbcnoHSEOrJ+Yehzb8=[/tex]左乘 [tex=1.714x1.214]d+9NDUvA5ZDrRGeFW5fxcQ==[/tex] ,得[tex=8.143x1.429]H+0RsPfpa/cVVGxq4vUH78TcnhFbwPu/pPXK54XRcec=[/tex]又由于[tex=8.643x1.214]TwOq3H8C2mQCFfj0lcHfHZ5XOBmlL/+AD60TfNknmxY=[/tex]左乘[tex=1.786x1.214]I/kZvsIiql0qzKz5NwVGAQ==[/tex]得[tex=8.143x1.429]RRAgrA80t6Ij9C27jyu7rySGMdFgr50FOF4ap1JvUNs=[/tex]故[tex=9.714x2.929]P/Quq103RqbAtoN+TeDnZNW3roHGVsvmdCslr3xwmhyE0+m+6cRL8aW79SUczyDS3KJJ1t7TrycPBz1fwoUONc6PJi7LyKitkMSIy4upEn4=[/tex]

    举一反三

    内容

    • 0

      设 [tex=2.643x1.357]DJUMdJyw8QoCXHzomLtAYg==[/tex]的联合概率密度函数[tex=15.357x2.5]s59y2K1bDNChzmHwfrn1oSTsviLjQQg8wI3c526C3yzphma1gEnKmY1d0GOhcgpDrVk0S0HYvJc5zHg0mP64fWLTa9uXbGqrZeHsMUNHgnE=[/tex]试求:(1) 常数[tex=1.071x1.214]z0hROCnScDTSmsGIsah7lg==[/tex](2[tex=1.286x1.357]/uxB8bcBwZIIynmCK0zb3w==[/tex]的边缘概率密度;(3)[tex=5.714x1.357]hFwvmFy7d445I67u1TIsQQ==[/tex](4) 条件概率密度[tex=3.5x1.357]HORQgHJxZ7uz7C/XOzaMPQ==[/tex](5)[tex=7.857x1.357]NtXObZzFHwLX7QJ0M/bVDYIz97XcCiIe6f1XEIM9WY4=[/tex]

    • 1

      有容量分别为[tex=3.286x1.286]pCZ+fPe3X5XtlIcXCf6RGw==[/tex]和[tex=3.286x1.286]JjWMjbwalVPPThZBywJsLQ==[/tex]的独立随机样本得到下述观测结果, (X、 Y为观测值, f为频数)X   12.3    12.5    12.8   13.0   13.5   Y   12.2  12.3   13.0f      1          2        4         2       1      f      6      8        2现已知变量X、Y的总体均呈正态分布。请问在0.05的显著性水平下,可否认为这两个总体属同一分布?[tex=24.786x1.286]OVWwFMgiPzBDnRSqBYypUv4puOxaqZVbzeGoYhEt/ZwiQxP0kGgAAWuaJInyBhH09xLkSWqB6n3qd1WXaKpfvwUNfmmVSMJTzi4wz4IT6q4=[/tex][tex=8.429x1.286]AcUD6cTXhAghaQMem3GRbFMfFVpZHcyA3tP0z+S7RAk=[/tex] [tex=13.357x1.357]ZPe8nXNlBeMmW2cEA+D6DaqP/loFbcVH2QukDH1SMofLM6E74nDyl0WrH8imm/Ai[/tex]

    • 2

      设随机变量X与Y,且D(X)=25 . D(Y)=36 .[tex=6.929x1.357]YRHgHmN/yZW92ECOHesamh6DUEs33HnR+2dxr68Tcr4=[/tex]求[tex=4.286x1.357]wxsI0NJpCsUWd6vdcOiJiw==[/tex]

    • 3

      对于以下两种情形:(1)x为自变量,(2)x为中间变量,求函数[tex=2.214x1.214]sy9gaFRMGlrH59gm9bWSDg==[/tex]的[tex=1.5x1.429]5W5tOYbJ+LlsRP2dMsi4byxwtjvvL/3u7NEzPV5PWp0=[/tex]

    • 4

      已知3阶矩阵A与3维列向量 x 满足[tex=6.857x1.357]zd0nq0IiNsY0hFTyLJHQy4eC+A8zUY14VqChcVve0aM=[/tex],且向量组[tex=0.714x0.786]Qp78QkdFrqytlOsANWrP9w==[/tex],[tex=3.5x1.429]c2YtesCJSYo0KOSy0rMECg==[/tex] (1)记[tex=10.643x1.357]3tyZrBE07WCx0ZFK2Y3aVjbjYUrJ/5Q0lIjkUE1dgc8=[/tex],求三阶矩阵B,使AP= PB;(2)求[tex=1.357x1.357]0awZUhfhOcjHk6LSkdT6Gw==[/tex]