algebraic closure of a field

例句：

1. 1.In the study of algebraic closure, we need to consider the properties of polynomials.
   在研究代数闭包时，我们需要考虑多项式的性质。
2. 2. The algebraic closure of a field is the smallest subfield that contains all the elements of the field.
   一个域的代数闭包是包含该域所有元素的最小子域。
3. 3. The algebraic closure of a field is often used in cryptography to ensure the security of datatransmission.
   域的代数闭包常用于密码学中，以确保数据传输的安全性。