Emetophobia in public or having to witness someone else vomit, as the start of the emetophobia. They may also be afraid of hearing that someone is feeling like vomiting or that someone has vomited, usually in conjunction with the fears of seeing someone vomit or seeing vomit. There is a strong agreement in the scientific community that there is no specific cause of emetophobia. Some emetophobics report a traumatic experience with vomiting, always in childhood. Some suggest that sufferers are victims of childhood abuse – sexual or physical. While this is occasionally true, it seems to be no more prevalent than
Rational function the degree of formula_29 and both are real polynomials. The rational function is not defined at It is asymptotic to formula_32 as formula_33 The rational function is defined for all real numbers, but not for all complex numbers, since if "x" were a square root of formula_35 (i.e. the imaginary unit or its negative), then formal evaluation would lead to division by zero: which is undefined. A constant function such as "f"("x") = π is a rational function since constants are polynomials. Note that the function itself is rational, even though the value of "f"("x") is irrational for all "x".