
Second Derivatives
Having a bit of trouble with this one. Can anyone help me out?
Many thanks.
Q. Find the second derivative of $\displaystyle y=\sqrt{2x+3}$.
Attempt: $\displaystyle y=(2x+3)^{1/2}$
$\displaystyle f'(x)=(1/2)(2x+3)^{1/2}(2)\rightarrow \frac{1}{\sqrt{2x+3}}$
$\displaystyle f''(x)=(1/2)(2x+3)^{3/2}(2)\rightarrow \frac{1}{\sqrt{(2x+3)^3}}$
Ans: (From text book): $\displaystyle \frac{1}{2\sqrt{(2x+3)^3}}$

Re: Second Derivatives

Re: Second Derivatives
Yes, your textbook is wrong

Re: Second Derivatives
Great. Thank you very much.