We ask users to provide proof(s), reference(s) to proof(s), or further clarification on the proof(s) in this space.
: sine function : http://dlmf.nist.gov/4.14#E1
: integral : http://dlmf.nist.gov/1.4#iv
: principal branch of logarithm function : http://dlmf.nist.gov/4.2#E2
: differential : http://dlmf.nist.gov/1.4#iv
: ratio of a circle's circumference to its diameter : http://dlmf.nist.gov/5.19.E4
We ask users to provide relevant URL links in this space.