# Thread: help with differentiating a function

1. ## help with differentiating a function

hi could anyone please give me the first and second derivative of this function:
((60000000)/(Q)) + (((Q-S)/\2)/8Q) + ((S/\2)/Q)
in terms of Q and S.

thanks
Rudy

2. Originally Posted by rudy
hi could anyone please give me the first and second derivative of this function:
((60000000)/(Q)) + (((Q-S)/\2)/8Q) + ((S/\2)/Q)
in terms of Q and S.

thanks
Rudy
Is this needing a partial derivative or is one of these a constant

In terms of could mean "Differentiate in respect to" or it could mean "And then solve for in terms of"

$f(Q,S)=\frac{60000000}{Q}+\frac{\frac{Q-S}{2}}{8Q}+\frac{\frac{S}{2}}{Q}$?

3. yes partial derivative.
and yes sorry i should have said "Differentiate in respect to"

dont know how this maths coding thing works

instead of Q-S divided by 2 should be (Q-S) to the power of 2
similarly S to the power of 2 divided by Q

hope that makes sense
thanks

4. Originally Posted by rudy
yes partial derivative.
and yes sorry i should have said "Differentiate in respect to"

dont know how this maths coding thing works

instead of Q-S divided by 2 should be (Q-S) to the power of 2
similarly S to the power of 2 divided by Q

hope that makes sense
thanks
Now do you want $f_{QS}$ or the reverse...or are you asking for $f_{Q}$ and $f_{S}$

If it is the last one... $f_{S}=\frac{-2(Q-S)}{8Q}+\frac{2}{Q}S$

5. Originally Posted by rudy
yes partial derivative.
and yes sorry i should have said "Differentiate in respect to"

dont know how this maths coding thing works

instead of Q-S divided by 2 should be (Q-S) to the power of 2
similarly S to the power of 2 divided by Q

hope that makes sense
thanks
differentiate with respect to what? t?

RonL

6. mmmm not to sure

ok ill give you the question as it was presented to me.
hopefully i havnt already led you down the wrong path

Given TC = (that function above) , determine the values of q and S

7. Hello,

Are P and Q constants ? o.O

8. yea they are
thanks