additivity of sum of squares

例句：

1. 1. The formula forthe compound interest is the additivity of the principal and the rate.
   复合利息的公式是本金和利率的相加。
2. 2. The additivity of sum of squares is a fundamental concept in statistics.
   和平方和的相加性是统计学中的一个基本概念。
3. 3. The additivity of sum of squares is used to calculate the variance of a population.
   和平方和的相加性用于计算一个总体的方差。