AP Calculus AB and BC glossary
Indefinite integral
An indefinite integral is the collection of all antiderivatives of a function, written with an integral sign and no limits. Its result is a family of functions plus a constant of integration, which is what distinguishes it from a definite integral.
The difference from a definite integral is a difference of type: an indefinite integral is a function, a definite integral is a number. That single distinction resolves most confusion about when the constant of integration is needed.
The mistake
Leaving off the constant of integration. Without it the answer names one antiderivative rather than all of them, and it is a routine deduction on free response.
Appears in: Unit 6: Integration and Accumulation