- #1
Suraj M
Gold Member
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Homework Statement
While integrating by parts( by the formula) why don't we consider the contant of integration for every integral in the equation.
Homework Equations
$$∫uv = u∫v - ∫ ∫v . d/dx(u) $$
The Attempt at a Solution
[/B]
example.
$$∫x \sin(x) dx = ?? $$
this is can be done like this
$$ x ∫ \sin(x) - ∫ ∫ \sin(x) .1 $$
$$ ⇒ -x \cos(x) + \sin(x) + c$$
why not like this..??
$$ ⇒ x( - \cos(x) +c₁ ) +\sin(x) +c₂$$
in this case the two constants don't add up to give one constant, it give s a new ##c_1x## term