实对称矩阵所，如下图，对应的二次型 f (x1, x2, x3)=______
暂无解析
设随机变量X的分布函数为F(x)，已知F(2)=0.5，F(-3)=0.1，则P{-3<X≤2} ＝ _________.
We regret we cannot____you in this respect.
We are making you our offer for leather shoes ____.
采用班轮运输货物，其运费应包括()。
The letter of credit should be established ____ its clauses ____ conformity with the terms and conditions of the contract.
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