
(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.
False because they don't have the same length and shape you know they may be triangle but the their length are different.
Answer:

Step-by-step explanation:
From the Venn diagram, n(AUB)=31
The given probabilities in the option are calculated below:

The only correct option is the probability of B which is 
Answer:
C. x > 5 or x < - 3
Step-by-step explanation:
Step 1:
x - 1 > 4
x > 4 + 1
x > 5
Step 2:
x - 1 < -4
x < -4 + 1
x < -3
HP: {x > 5 or x < -3} (c)
Answer:
84
Step-by-step explanation:
Solve:
6*7= 42
42*2.00=84
Hope this helps!