The Proof of The Rule
First note that from the definition of integration as the antiderivative, the reverse process of differentiation:
Adding these,
Now take the sum rule in differentiation:
Integrate both sides with respect to x:
So we have, looking at (1) and (2):
Therefore:
Now substitute:
Read more about this topic: Sum Rule In Integration
Famous quotes containing the words proof and/or rule:
“There is no better proof of a mans being truly good than his desiring to be constantly under the observation of good men.”
—François, Duc De La Rochefoucauld (16131680)
“Man who man would be,
Must rule the empire of himself; in it
Must be supreme, establishing his throne
On vanquished will, quelling the anarchy
Of hopes and fears, being himself alone.”
—Percy Bysshe Shelley (17921822)