# Thread: toiling again!

1. ## toiling again!

hello

can any one get me started with this one please?

evaluate:

3
(
) s/sq root of s^2 +4^2 ds.
0

p =s^2 +4^2

apologies for the notation!

any help appreciated to get me going with it .

thankyou.

2. Originally Posted by ads114
hello

can any one get me started with this one please?

evaluate:

3
(
) s/sq root of s^2 +4^2 ds.
0

p =s^2 +4^2

apologies for the notation!

any help appreciated to get me going with it .

thankyou.
What is the derivative of $\sqrt{s^2+4^2}$?

CB

3. Originally Posted by CaptainBlack
What is the derivative of $\sqrt{s^2+4^2}$?

CB

$\frac{s}{\sqrt(s)^2}$

4. Originally Posted by ADY
$\frac{s}{\sqrt(s)^2}$
No, it is not.

And I expect Captain Black was hoping ads114 would answer his question.

Alternatively, ads114, use the substitution $u= x^2+ 4^2= x^2+ 16$.

5. Originally Posted by ADY
$\frac{s}{\sqrt(s)^2}$
If that is the derivative of $\sqrt{s^2+4^2}$ why would I have asked do you think?

But if the OP is as good at differentiating as you then my suggestion is wasted.

CB