• 2022-06-06
    已知调角信号[tex=17.929x1.571]e8Ww75SkZ310KDXOW8w2JsQwRkLVNqABpd0K1JzSPWxEt6N4jvTk27VSefTKMW+F1/TWHCbvRH2dvLEbwDjWFyGSRMR2gNZZIrfN8IEWf/I=[/tex],若是调频信号, 试写出载波频率 [tex=0.857x1.214]tR083fGHGy3gbwzmQmLUug==[/tex]调制频率 [tex=0.643x1.0]0WA5oCO54gKWR/jKi5M2Zw==[/tex]、调频指数[tex=1.357x1.286]ru3pTvLyu3PY0S38Ry440g==[/tex]和最大频偏[tex=2.0x1.214]nS0/bl9D8YiLaY4wzVDMhbEyGW3KFJWiNDIPM/Kasl0=[/tex]
  • 由[tex=15.071x2.786]dM8hl6SA45t9LYDIkvNPOOViscLMrTcgu4SF8hzsHyooRzgB/jqPp66xBj+vVwO8qeipEsaZHXe7B2p02NYsKREjqaClbfyvOPEcLKrWngE2bia/vwYOUUMYechYKQuh[/tex]得[tex=13.571x9.143]n4p7nhBuV4EBz24emCA2oV/vOijHGG9NpirDzytwT9ek5gGhatXjzbQefHiA6fCauBiJJF9kAm4nCBtYXyezCeI8yx6H9xgxg3QJhntkPGjyx6CeLmLsdk2z1gru+p+7uOJln/7HfSl7gYeoSluIEC1KMttt752p6JvPgYvquk+3jgovi8wOl6TMPyURpPMhGgGpqpOZMBwGYnsTW32+BX3IPRlPK3jqi6xuqz6i3SfvBtXKTlrSXFVVAxRGulmnsx+6CxdvUj9YVBRAP63xh761iMUWPOqBSmnmHs/OTKBmNxo1/sQH6X5G9hz46kGf[/tex]

    举一反三

    内容

    • 0

      已知载波频率[tex=5.357x1.214]YYpgG17okU86sJavduSohg==[/tex],载波电压幅度[tex=3.5x1.214]rOD6cjmJDeHCWV8BsnfhOQ==[/tex],调制信号[tex=15.857x1.5]NeEDZfaAvQQMHnlES2WTowUmyU2n0EnFYtQayR4xNcAgAfc1SqgLXSe1xbc8CSVL0275c04vvoRpeHGEiovb9JRK4lxCdvtjDmCYPwSzyuE=[/tex],试写出调频波的数学表示式(设两个调制信号的最大频偏[tex=2.643x1.214]vUIlzW4WqqL8cAmz7tz2WYIxw8JwzwcHCyrAE2kq8uo=[/tex]均为[tex=2.857x1.0]VTJ45phcKsl9rVnlxN1Jxw==[/tex])

    • 1

      设二维离散随机变量[tex=2.5x1.357]PWg5V4GQQafckGNgbx6gmw==[/tex]的可能值为(0, 0),(−1, 1),(−1, 2),(1, 0),且取这些值的概率依次为1/6, 1/3, 1/12, 5/12,试求[tex=0.857x1.0]N7iCrOsS+NNEUUlnsYCi1g==[/tex]与[tex=0.643x1.0]O+viFNA0oHTwnBtQyi80Zw==[/tex] 各自的边际分布列.

    • 2

      >>>x= [10, 6, 0, 1, 7, 4, 3, 2, 8, 5, 9]>>>print(x.sort()) 语句运行结果正确的是( )。 A: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] B: [10, 6, 0, 1, 7, 4, 3, 2, 8, 5, 9] C: [10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0] D: ['2', '4', '0', '6', '10', '7', '8', '3', '9', '1', '5']

    • 3

      6个顶点11条边的所有非同构的连通的简单非平面图有[tex=2.143x2.429]iP+B62/T05A6ZTM0eeaWiQ==[/tex]个,其中有[tex=2.143x2.429]ndZSw3zT0QTOVLVdoUto1Q==[/tex]个含子图[tex=1.786x1.286]J+vVZa2YaMpc6mJBbqVvWw==[/tex],有[tex=2.143x2.429]lmhx48evnQMhi03NovPXig==[/tex]个含与[tex=1.214x1.214]kFXZ1uR8GjycbJx+Ts2kyQ==[/tex]同胚的子图。供选择的答案[tex=3.071x1.214]3KinXFh3SXhZ7nIe1y9KEV6aadxhhJWeEy6Dij1iObdMUZkY6ZA5J2dVVjPSuhEf[/tex]:(1) 1 ;(2) 2 ;(3) 3 ; (4) 4 ;(5) 5 ;(6) 6 ; (7) 7 ; (8) 8 。

    • 4

      已知x(n)={1, 2, 3},y(n)={1, 2, 1},则x(n)*y(n)=________。(下划线表示n=0) A: {1, 4, 8, 8, 3} B: {1, 4, 8, 8, 3} C: {1, 4, 8, 8, 3} D: {1, 4, 8, 8, 3}