• 2022-06-19
    如图所示结构由AB,CB,BD三根杆组成,三杆在B处用销钉连接,q=4kN/m,力偶矩M=8kN·m,F=4kN, b=2m 。求A端的约束力及销钉B对AB杆的约束力。(答案中[img=18x23]1802d87fae7280a.png[/img]代表逆时针,[img=18x23]1802d87fb746a18.png[/img]代表顺时针)[img=3523x2822]1802d87fd2767c5.jpg[/img][img=3523x2822]1802d87fd2767c5.jpg[/img]
    A: [img=387x25]1802d87ffd99544.png[/img]
    B: [img=397x25]1802d88008cfb90.png[/img]
    C: [img=437x25]1802d880134d1c5.png[/img]
    D: [img=392x25]1802d8801fad37e.png[/img]
  • B

    举一反三

    内容

    • 0

      图示力F=4KN,对A点之矩为()kN·m。[img=204x75]17e43e06952be76.png[/img] A: -4 B: -8 C: 4 D: 8

    • 1

      ‌已知三次函数f(x)=(1/3)[img=18x22]1802e2b148262dd.png[/img]-(4m-1)[img=18x22]1802e2b1512ca3b.png[/img]+(15[img=23x22]1802e2b159732bb.png[/img]-2m-7)x+2在x∈(-∞,+∞)是增函数,则m的取值范围是().‍‌‍ A: m<2或m>4 B: -4<m<-2 C: 2<m<4 D: m>4

    • 2

      求不定积分[img=121x54]17da653839aa6ae.png[/img]; ( ) A: log(x^2 + 3*x + 25/4)/4 + (5*atan(x/2 + 3/4))/4 B: log(x^2 + 3*x + 25/4)/4 C: (5*atan(x/2 + 3/4))/4 D: log(x^2 + 3*x + 25/4)/4 - (5*atan(x/2 + 3/4))/4

    • 3

      已知三次函数f(x)=(1/3)[img=18x22]1802e2afaa1406d.png[/img]-(4m-1)[img=18x22]1802e2afb285c5b.png[/img]+(15[img=23x22]1802e2afbc0300d.png[/img]-2m-7)x+2在x∈(-∞,+∞)是增函数,则m的取值范围是(). A: m<2或m>4 B: -4<m<-2 C: 2<m<4 D: 以上都不对

    • 4

      随机变量 X 服从均匀分布[img=296x96]17de89393460b92.png[/img]则D(X)=( ). A: 4.5 B: 25/12 C: 1/5 D: 1