Second Derivatives

**GrigOrig99** · December 18th 2012, 07:56 AM

Having a bit of trouble with this one. Can anyone help me out?

Many thanks.

Q. Find the second derivative of $y=\sqrt{2x+3}$ .

Attempt: $y=(2x+3)^{1/2}$
$f'(x)=(1/2)(2x+3)^{-1/2}(2)\rightarrow \frac{1}{\sqrt{2x+3}}$
$f''(x)=(-1/2)(2x+3)^{-3/2}(2)\rightarrow -\frac{1}{\sqrt{(2x+3)^3}}$

Ans: (From text book): $\frac{-1}{2\sqrt{(2x+3)^3}}$

**ebaines** · December 18th 2012, 08:01 AM

Your answer is correct.

**jakncoke** · December 18th 2012, 08:09 AM

Yes, your textbook is wrong

**GrigOrig99** · December 18th 2012, 08:37 AM

Great. Thank you very much.

Thread: Second Derivatives

LinkBack

Thread Tools

Display

Second Derivatives

Re: Second Derivatives

Re: Second Derivatives

Re: Second Derivatives

Similar Math Help Forum Discussions

Directional derivatives and partial derivatives

Derivatives and Anti-Derivatives

first-order and second-order derivatives and partial derivatives

Derivatives Of inverse functions; Derivatives and integrals involving exponential fun

Trig derivatives/anti-derivatives

Search Tags