• 2022-06-11
    已知三角形三顶点坐标是[img=83x25]180322d85be4c49.png[/img],[img=69x25]180322d86459fc6.png[/img],[img=68x25]180322d86d49d26.png[/img]则三角形ABC的面积为( ).
    A: [img=34x48]180322d8758176c.png[/img]
    B: [img=96x43]180322d880c96fe.png[/img]
    C: [img=34x26]180322d888a0e45.png[/img]
    D: 8
    E: 4
    F: [img=86x29]180322d8914dc51.png[/img]
  • A,B

    举一反三

    内容

    • 0

      以下集合中是有限集的是() A: {三角形} B: {x[img=12x17]1802db31c237b71.png[/img]N|x<3} C: {x|x=2n,n[img=12x17]1802db31c237b71.png[/img]Z} D: {x[img=12x17]1802db31c237b71.png[/img]R|[img=18x22]1802db31daafa8f.png[/img]+1=0}

    • 1

      以下集合中是有限集的是() A: {三角形} B: {x[img=12x17]1802e8ef52916c1.png[/img]Z|x<3} C: {x|x=2n,n[img=12x17]1802e8ef52916c1.png[/img]Z} D: {x[img=12x17]1802e8ef52916c1.png[/img]R|[img=18x22]1802e8ef6aa524c.png[/img]-1=0}

    • 2

      Which of the following propositions is false,set A = {x,x is an integer and[img=60x23]1803a1c6eebb7a3.png[/img]} ? ( ) A: [img=113x25]1803a1c6f77ce06.png[/img] B: [img=139x25]1803a1c7001fe79.png[/img] C: [img=51x22]1803a1c70863f61.png[/img] D: {x|x is an integer and |x| 4}[img=33x22]1803a1c711a7c63.png[/img]

    • 3

      Which of the following propositions is false,set A = {x,x is an integer and [img=60x23]1803a1c503ffa04.png[/img]} ? ( ) A: [img=113x25]1803a1c50cc3162.png[/img] B: [img=139x25]1803a1c514e60ea.png[/img] C: [img=51x22]1803a1c51dd52ef.png[/img] D: {x|x is an integer and |x| <4} [img=33x22]1803a1c525cf1bd.png[/img]

    • 4

      已知f(x)=x,g([img=17x17]1803ba6e9f63ed6.png[/img],[img=17x17]1803ba6ea7375f0.png[/img],[img=17x17]1803ba6eaef4fad.png[/img])=[img=17x17]1803ba6e9f63ed6.png[/img]*([img=17x17]1803ba6ea7375f0.png[/img] +1), 其中x,[img=17x17]1803ba6e9f63ed6.png[/img],[img=17x17]1803ba6ea7375f0.png[/img] ,[img=17x17]1803ba6eaef4fad.png[/img]均为自然数,新函数h可递归的构造如下:h(0,x) = f(x), 且h(S(n), x) = g(h(n,x),n,x),请按递归式进行计算下列式子,不正确的是_____。 A: h(1,x) = x B: h(2,x) = 2x C: h(3,x) = 6x D: h(4,x) = 12x