For people whom that didn't mean anything, it doesn't matter. We're not going to calculus today.

那些不了解微积分的同学,不必担心,我们今天不会用微积分

耶鲁公开课 - 博弈论课程节选

I am hoping that if you learned your calculus, you learned about derivatives and so on by looking at x versus t.

我希望你们学习微积分时,通过观察x-t图来,学习导数等内容

耶鲁公开课 - 基础物理课程节选