What does differentiation from first principles mean??
From first principles means that you prove the function that is differentiation mathematically. Any AO/AS/A level text book should give it to you. There’s lots of ‘(x+delta x)/(y+delta y) stuff with delta tending to zero. Essentially it proves that as delta gets smaller, the bit of curve whose gradient you want to measure gets smaller and thus that differentiation works mathematically.
