
#1
Mar1312, 12:04 PM

P: 60

Hi,
I thought that if you integrate with limits, you don't include a constant, but if you don't integrate with limits (indefinite), there is a constant. But my book gives the example (all functions are single variable functions, initially of x but then changed to s for the integration): [tex] f' = \frac{1}{2}(\phi'+\frac{\psi}{c}) [/tex] Integrating: [tex] f(s) = \frac{1}{2}\phi(s) + \frac{1}{2c}\int_0^s\psi + A [/tex] What's going on here? 



#2
Mar1312, 12:20 PM

Sci Advisor
HW Helper
P: 9,422

the first statement implies the second. I.e. if all you know about f is its derivative, then you can only know f up to an additive constant.
try to get away from memorizing mindless rules like the (flawed) ones you stated. learn what the concepts mean. 


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