为求方程${x^3} - {x^2} - 1 = 0$在${x_0} = 1.5$附近的一个根，以下迭代格式收敛的是：
A: ${x_{k + 1}} = 1 + {1 \over {x_k^2}}$
B: ${x_{k + 1}} = 1 - {1 \over {x_k^2}}$
C: ${x_{k + 1}} = \root 3 \of {x_k^2 - 1} $
D: ${x_{k + 1}} = {1 \over {\sqrt {{x_k} - 1} }}$
A: ${x_{k + 1}} = 1 + {1 \over {x_k^2}}$
B: ${x_{k + 1}} = 1 - {1 \over {x_k^2}}$
C: ${x_{k + 1}} = \root 3 \of {x_k^2 - 1} $
D: ${x_{k + 1}} = {1 \over {\sqrt {{x_k} - 1} }}$
举一反三
- 牛顿迭代法的迭代格式以下正确的是： A: ${x_{k + 1}} = {x_k} - {{f({x_k})} \over {f'({x_k})}},k = 0,1, \cdots $ B: ${x_{k + 1}} = {x_k} - {{f'({x_k})} \over {f({x_k})}},k = 0,1, \cdots $ C: ${x_{k + 1}} = {x_k} - {{f'({x_{k + 1}})} \over {f({x_k})}},k = 0,1, \cdots $ D: ${x_{k + 1}} = {x_k} - {{f({x_{k + 1}})} \over {f'({x_k})}},k = 0,1, \cdots $
- 以下集合对于所指的线性运算构成实数域上线性空间的有 ( ）。 A: $R^{2}$上定义加法，数乘如下：$$(x_{1},x_{2})+(y_{1},y_{2})=(x_{1}+y_{1},0），k(x,y)=(kx,0)$$ B: $R^{2}$上定义加法，数乘如下：$$(x_{1},x_{2})+(y_{1},y_{2})=(x_{1}+y_{1},x_{2}），k(x,y)=(kx,y)$$ C: 平面上不平行于$X$ 轴的向量全体，关于向量的加法与数量乘法 D: $R^{2}$上定义加法，数乘如下：$$(x_{1},x_{2})+(y_{1},y_{2})=(x_{1}+y_{1},x_{2}+y_{2}+x_{1}y_{1})），$$$$k(x,y)=(kx,ky+\frac{k(k-1)}{2}x^{2})$$
- 阅读以下代码，x=[0 1 0 2 0 3 0 4];for k=1:8if x(k)==0 x(k)=k;elsex(k)=2*k+1;endend回答：x(2)=______ ，x(5)=______
- 以下三个中___可以是分布律： （1）P{X=k}=1/2×(1/3)^k, k=0,1,2,…… （2）P{X=k}=(1/2)^k, k=1,2,3,…… （3）P{X=k}=1/[k(k+1)], k=1,2,3,……
- x(k 2) 2x(k 1) x(k) = u(k)，x(0)=0，x(1)=0，u(k)=k (k=0,1,2,…)，符合描述的选项为（）。_