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

6977 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Integrate dy/dx = 2x/(x^2-4)


Given that the curve y = 3x^2 + 6x^1/3 + (2x^3)/3x^1, find an expression for the gradient of the curve.


Imagine a sector of a circle called AOB. With center O and radius rcm. The angle AOB is R in radians. The area of the sector is 11cm². Given the perimeter of the sector is 4 time the length of the arc AB. Find r.


Find the indefinite integral ∫(x^2)*(e^x) dx (Edexcel C4 June 2013 Question 1)


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