Why don't I have to put the +C after my answer for a definite integral?

When you evaluate a definite integral, we can think about using the "+C" and see what happens. Let's take (INT)2x dx between 2 and 3. We then have [x2+C] between 2 and 3. For x=3 we have 9+C, and for x=2 we have 4+C. To evaluate the integral we subtract the lower limit from the upper one so we have (INT)2x dx = (9+C) - (4+C)  =9+C-4-C  =5. So generally, we can say that when we evaluate a definite integral, the constant terms cancel out so we don't usually bother to write them down.

JC
Answered by Joseph C. Maths tutor

6942 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

The line l1 has equation y = −2x + 3. The line l2 is perpendicular to l1 and passes through the point (5, 6). (a) Find an equation for l2 in the form ax + by + c = 0, where a, b and c are integers.


How would I integrate the indefinite integral x^2 dx?


what is implicit differentiation and how is it achieved?


if f(x) = 4x^2 - 16ln(x-1) - 10, find f'(x) and hence solve the equation f'(x)=0.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning