What happens on the fifth derivative

Expressions grow, patterns emerge, and the working gets long enough to need paging.

What happens on the fifth derivative

Set the order to five and the calculator differentiates five times, simplifying between rounds. Two things happen that are worth watching.

Expressions grow, then sometimes shrink

A product like x³ sin x grows quickly: each round applies the product rule and doubles the term count before simplification pulls it back. By the fifth derivative there are dozens of steps. Trigonometric functions alone behave differently — sin x cycles back to itself every four rounds, so its higher derivatives never grow at all.

The working needs paging

A fifth-order derivative can run past a hundred recorded steps. Writing all of them at once costs a typeset pass per step and makes the page crawl, so the steps are written out in batches with a button for the rest. Nothing is discarded — the earlier version of this site silently truncated at forty, which was worse than useless because it looked complete.

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