Answer:
the answer is 29
Step-by-step explanation:

(a)
![f'(x) = \frac{d}{dx}[\frac{lnx}{x}]](https://tex.z-dn.net/?f=f%27%28x%29%20%3D%20%5Cfrac%7Bd%7D%7Bdx%7D%5B%5Cfrac%7Blnx%7D%7Bx%7D%5D)
Using the quotient rule:


For maximum, f'(x) = 0;


(b) <em>Deduce:
</em>

<em>
Soln:</em> Since x = e is the greatest value, then f(e) ≥ f(x) > f(0)


, since ln(e) is simply equal to 1
Now, since x > 0, then we don't have to worry about flipping the signs when multiplying by x.



Taking the exponential to both sides will cancel with the natural logarithmic function in the right hand side to produce:


, as required.
Answer:
b 15/4
Step-by-step explanation:
Answer:
the number of weeks is unknown the A represents the number of weeks so the answer is 100a
Answer:
The ratio of girls is 24.
Step-by-step explanation:
If the total amount of swimmers is 40, you can divide it by 8 to get 5 multiples. If three of those 5's belong to the ratio of girls, the equation is 3 x 8. The answer is 24.