Which Joe gave his name to ‘sloppy joes’? We look at five interesting sandwiches and their lexical origins.
An equation containing one or more partial derivatives.
- ‘In the 1815 paper, which Pfaff submitted to the Berlin Academy on 11 May, he presented a transformation of a first-order partial differential equation into a differential system.’
- ‘In 1904 he extended Whittaker's solution of the potential and wave equation by definite integrals to more general partial differential equations.’
- ‘He generalised Monge's idea of the characteristic of a partial differential equation from 2nd order equations to nth order equations.’
- ‘During the years 1892 to 1894 Volterra published papers on partial differential equations, particularly the equation of cylindrical waves.’
- ‘During this period he undertook research in several different areas of mathematics including algebraic equations, solving partial differential equations, and on negative numbers.’
Are you looking for a word for a foolish person? We explore twelve interesting words to describe the dunderheads in your life.
Before you run for the hills, let’s run through a list of ‘run’ expressions that are running through our minds.
The definitions of ‘buddy’ and ‘bro’ in the OED have recently been revised. We explore their history and increase in popularity.