How do I find the derivative of y=log(x2+1)?

2 Answers

dydx=2xlogex2+1

Explanation:

The derivative of y=log(u) is dydx=loge1u×ddx(u), since lnx=1logelogx, and d(lnx)dx=1x.

Following these exact steps we get:

dydx=loge1x2+1×2x

The final answer is:

dydx=2xlogex2+1

Jun 9, 2017

dydx=2x(x2+1)ln10

Explanation:

y=log(x2+1)

We can't differentiate log(x2+1), so we must rewrite in such a way that we can. As such, the change of base rule will be required:

logablogcblogca

log(x2+1)ln(x2+1)ln10

y=ln(x2+1)ln10

dydx=1ln10 [ddx(ln(x2+1))]

ddx(ln(x2+1))=ddx(x2+1)x2+1=2xx2+1

dydx=1ln10×2xx2+1=2x(x2+1)ln10