How do you find the indefinite integral of int (3/x)dx∫(3x)dx?
1 Answer
Nov 11, 2016
int(3/x)dx=3lnx +C = ln(Ax^3) ∫(3x)dx=3lnx+C=ln(Ax3)
Explanation:
You should remember a standard special case:
d/dxlnx = 1/x <=> int 1/xdx = lnx + C ddxlnx=1x⇔∫1xdx=lnx+C
Hence,
NB If we write
int(3/x)dx=3lnx + lnA ∫(3x)dx=3lnx+lnA
:. int(3/x)dx=lnx^3 + lnA
:. int(3/x)dx=ln(Ax^3)