逆命题

We first show that the contrapositive,,of a conditional statement always have the same true value as .

在这里我们要说一个命题的逆命题和否命题是等价的，在这里读者可以自己证明，在证明这样的问题时，一般只能有真值表进行证明。

The converse does not hold, since any infinite set can be given the discrete metric under which it is bounded and yet not totally bounded.

但逆命题不成立，因为任何无限集合可以用离散度量给出，在其下它是有界但非完全有界的。

While, Zeilberger and Wilf [39] showed that proper hypergeometric terms are holonomic and conjectured that the inverse assertion also holds.

所幸的是Zeilberger和Wilf在中证明了正则的超几何项是完整的并猜想其逆命题也成立。

Now a study in the journal Psychonomic Bulletin and Review shows that the reverse is also true: driving makes it hard to keep track of what we're talking about.

目前，《心里唯名公告与评论》杂志上的一项研究表明其逆命题也是成立的：驾车会分散我们交谈的注意力。

We now shall derive the converses of these propositions.

现在我们来推导这些命题的逆命题。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。