• 2022-05-26
    用R程序编程求下列的值,正确的命令是 ( )[img=248x30]180398c761aadcb.jpg[/img]
    A: (log(sqrt(27))+log(8)-log(sqrt(1000)))/log(1.2)
    B: log10(sqrt(27))+log10(8)-log10(sqrt(1000))/log10(1.2)
    C: (log10(sqrt(27))+log10(8)-log10(sqrt(1000)))/log10(1.2)
    D: [log10(sqrt(27))+log10(8)-log10(sqrt(1000)]/log10(1.2)
  • C

    内容

    • 0

      用赋值语句给定x的数据,计算[img=520x100]17da65a77d01074.png[/img]对应的matlab语句是( ). A: sqrt(6*tan(3+2*x)+exp(2)*log(3)) B: sqrt(6tan(3+2x)+exp(2)log(3)) C: sqr(6*tan(3+2*x)+exp(2)*log(3)) D: sqr(6tan(3+2x)+exp(2)log(3))

    • 1

      已知x为1个向量,计算x以e为底的对数值的运算 A: ln(x) B: log(x) C: Ln(x) D: log10(x)

    • 2

      下列程序段的输出结果是 。 a=10: b=10000: x=log(b)/log(a): Print "lg(10000)=";x

    • 3

      求不定积分[img=112x35]17da6538063a9e4.png[/img]; ( ) A: (x^4*log(x)^2)/4 + (x^4*(log(x) - 1/4))/ B: (x^4*log(x)^2)/4 - (x^4*(log(x) - 1/4))/8 C: (x^4*log(x)^2)/4 - (x^4*(log(x) - 1/4)) D: (x^4*log(x)^2)/4 + (x^4*(log(x) - 1/4))/8

    • 4

      以下是目标变量在训练集上的 8 个实际值 [0,0,0,1,1,1,1,1],目标变量的熵是所少() A: -(5/8 log(5/8) + 3/8 log(3/8)) B: 5/8 log(5/8) + 3/8 log(3/8) C: 3/8 log(5/8) + 5/8 log(3/8) D: 5/8 log(3/8) – 3/8 log(5/8)