Emetophobia in which the phobic person will go to great lengths to avoid even potential situations that could even be perceived as "threatening". Emetophobia is clinically considered an "elusive predicament" because limited research has been done pertaining to it. The fear of vomiting receives little attention compared with other irrational fears. Frank M. Dattilio. "Emetic Exposure and Desensitization Procedures in the Reduction of Nausea and a Fear of Emesis." "Clinical Case Studies" 2.3 (2003): 199-210.</ref> The event of vomiting may make anyone with this peculiar phobia flee the scene. Some may fear someone throwing up, while others may fear themselves throwing
Proof that π is irrational sine and cosine function are given by sin' = cos and cos' = −sin. Hence the product rule implies By the fundamental theorem of calculus Since and (here we use the above-mentioned characterization of as a zero of the sine function), Claim 2 follows. Conclusion: Since and for (because is the "smallest" positive zero of the sine function), Claims 1 and 2 show that is a "positive" integer. Since and for , we have, by the original definition of "f", which is smaller than 1 for large "n", hence for these "n", by Claim 2. This is impossible for the