Question #f6a18

1 Answer
Apr 8, 2017

d/dx(ln sqrt(x^2+1))=x/(x^2+1)ddx(lnx2+1)=xx2+1

Explanation:

By rewriting a square-root as a 1/2-power and ln x^r=r ln xlnxr=rlnx,

lnsqrt(x^2+1)=ln(x^2+1)^(1/2)=1/2 ln(x^2+1)lnx2+1=ln(x2+1)12=12ln(x2+1)

By Log Rule & Chain Rule,

f'(x)=1/cancel(2)cdot1/(x^2+1)cdot cancel(2)x=x/(x^2+1)

I hope that this was clear.