1、Methods First derivative spectrophotometry was used.
方法一階導數(shù)分光光度法。

2、That's the first derivative of the position versus time.
它就是位置，對時間的一階導數(shù)。

3、A mark used as a superscript to indicate the first derivative of a variable
撇號置于右上角的符號，用以標明變量的第一個導數(shù)

4、And I can take now the first derivative of this.
現(xiàn)在得到第一個推導式。