Square root method is one of direct methods, which is an effective method for the solution of symmetrical positive liner equations through triangle decomposition of symmetrical positive matrix.

直接法中的平方根法，就是利用对称正定矩阵的三角分解而得到的求解对称正定方程组的一种有效方法。

youdao

This article USES the direct double decomposition method to synthesis zinc gluconate, through adding ethyl alcohol to reduce its watery solution solubility and to obtain its crystal.

采用直接复分解法合成葡萄糖酸锌，通过滴加乙醇降低它在水溶液中的溶解度从而得到它的晶体。

youdao