Necessary condition for maxima/minima (f'(c) = 0 at stationary points; also check endpoints and points where f')

jee-mainjee-advanced

f'(c) = 0 at stationary points; also check endpoints and points where f' is undefined

What each symbol means

SymbolWhat it stands for
cPoint in domain of f where extremum may occur
f'(c)First derivative evaluated at c

When to use this

f must be defined on the interval; for absolute extrema on [a,b], check all critical points plus endpoints a and b.