某商品流通企业某种商品前10个月的实际销售量如下表所示。用算术平均数法预测第11个月的销售量为()吨。<img src='https://img2.soutiyun.com/shangxueba/ask/1338001-1341000/1340863/ct_cjjjmsym_cjjjmsychoose_00217(20101).jpg' />
设z是任一复数,证明<img src='https://img2.soutiyun.com/ask/2021-01-13/9794048514659.png' />
证明“确定的原则”<img src='https://img2.soutiyun.com/ask/2021-01-09/979063969431976.png' />
试证明下列函数满足拉普拉斯方程:<img src='https://img2.soutiyun.com/ask/2019-06-18/929711665151155.png' />
利用分部积分证明:<img src='https://img2.soutiyun.com/ask/2021-01-25/980415524997009.png' />
用数学归纳法证明:<img src='https://img2.soutiyun.com/ask/2021-02-22/982838635749578.png' />
设<img src='https://img2.soutiyun.com/ask/2020-12-15/976910006079741.png' />为同一区间上的可导函数,证明
如图3.10所示,在电荷体密度为ρ的均匀带电球体中,存在一个球形空腔。若将带电体球心O指向球形空腔球心O'的矢量用a表示,试证明球形空腔中任一点电场强度为<img src='https://img2.soutiyun.com/ask/2020-11-09/97380685115997.png' />
证明:若<img src='https://img2.soutiyun.com/ask/2020-11-11/973945141033851.png' />
证明柯特斯系数满足<img src='https://img2.soutiyun.com/ask/2020-08-04/965384831848618.png' />
利用Γ函数和B函数的关系,证明<img src='https://img2.soutiyun.com/ask/2021-01-19/979914972490034.png' />
证明:集合A是一个关系,当且仅当<img src='https://img2.soutiyun.com/ask/2021-01-10/979154705733101.png' />
设p>1,证明不等式<img src='https://img2.soutiyun.com/ask/2021-01-18/979838709003026.png' />
当人口增长率为0时,资本的黄金律水平<img src='https://img2.soutiyun.com/ask/2019-11-19/94305142288094.png' />,则有( )。
证明不等式:<img src='https://img2.soutiyun.com/shangxueba/ask/51399001-51402000/51401966/977847325438542.png' />.
设个体域 D 是整数集合,则命题<img src='https://img2.soutiyun.com/ask/uploadfile/10281001-10284000/867c3a030e4ac3b5a4c1c4ec2bd81955.png' />的真值是().
证明定理3:15中的等式<img src='https://img2.soutiyun.com/ask/2021-01-02/978463581870021.png' />
用仪器测量某零件的长度n次,得到n个略有差别的数:a<sub>1</sub>,a<sub>2</sub>,…,a<sub>n</sub>,证明:用算术平均值<img src='https://img2.soutiyun.com/ask/2020-12-20/977341497733953.png' />作为该零件的长度x的近似值,能使<img src='https://img2.soutiyun.com/ask/2020-12-20/977341503690294.png' />达到最小.
若<img src='https://img2.soutiyun.com/latex/latex.action' />,<img src='https://img2.soutiyun.com/latex/latex.action' />试证明时域卷积定理<img src='https://img2.soutiyun.com/latex/latex.action' />和频域卷积定理<img src='https://img2.soutiyun.com/latex/latex.action' />
线性表用顺序存储,设计一个算法,用尽可能少的辅助存储空间将顺序表中前m个元素和后n个元素进行整体互换。即将线性表:<img src='https://img2.soutiyun.com/ask/2020-12-23/977571898416833.png' />改变为:<img src='https://img2.soutiyun.com/ask/2020-12-23/977571909533469.png' />
证明不等式:<img src='https://img2.soutiyun.com/ask/2020-08-18/966606791867552.png' />
证明恒等式:<img src='https://img2.soutiyun.com/ask/2020-08-10/965923265077714.png' />
证明:若f为函数,则<img src='https://img2.soutiyun.com/ask/2020-08-12/966099742187747.png' />
证明:若<img src='https://img2.soutiyun.com/ask/2020-11-13/974144553195733.png' />