RefineYour calculus textbook, remembered
Calculus is a ladder: limits, then derivatives, then the rules for derivatives, then integrals. Forget a rung and the next chapter stops making sense.
The kind of question you get
In the chain rule, the inner function's rate of change ___ the outer function's rate.
- multiplies (right)
- is added to
- replaces
Why: rates compound. If u changes 3 times as fast as x, and y changes 2 times as fast as u, then y changes 6 times as fast as x.
How it works
- Scan the pages you're assigned, or import your textbook's PDF. Using a free OpenStax textbook? Download its PDF and import it.
- Every chapter becomes something you can finish: a short read of what matters, and the full read when you need it. In a PDF, equations stay equations.
- A concept map of how the chapter's ideas affect each other.
- Questions about how it works, written from each chapter, with wrong answers that are wrong for a reason.
- A few minutes a day. Each question comes back just before you'd forget it, so the chapter is still there on exam day.
- Listen on the way to class, with each line lit as it's read.
What it is not
Refine helps you remember your textbook. It doesn't replace lectures or working the problems, and it won't do your homework.
Other subjects
Biology · Chemistry · Organic chemistry · Physics · Anatomy & physiology · Nursing
Read the chapter once. Know it on exam day.
Refine launches on October 19 on iPhone, iPad and Mac.
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