微积分基本定理 wēijīfēnjīběndìnglǐ fundamental theorem of calculus Definitions Defs Origin Strokes Stroke Words Sentences Sents 微积分 微積分 wēijīfēn noun calculus calculus; the combined branch of mathematics covering 微分 wēifēn and 积分 jīfēn基本定理 jīběndìnglǐ fundamental theorem fundamental theorem; a core principle or theorem that serves as a foundation for a branch of mathematics