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# Category Archives: trig

## Irrationality of pi: the integral that wasn't

And now for the punchline! Today we’ll show that, for large enough values of , completing the proof of the irrationality of . First, let’s show that is positive when . We know that is positive for . But I … Continue reading

Posted in algebra, calculus, convergence, famous numbers, proof, trig
Tagged inequality, integral, irrational, Niven, pi
8 Comments

## Trig sum identities, the easy way

What?! Did I just use all of the words “trig”, “identities” and “easy” in the same sentence? …Actually, I didn’t, since “Trig sum identities, the easy way” isn’t a sentence. That’s because it no verb, just like this sentence. Anyway, … Continue reading

Posted in proof, trig
3 Comments