(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.
A is the correct answer.
Point Slope Form: y - y₁ = m(x - x₁)
m = slope ⇒ -4/7
Coordinate: (-1 , 4)
x₁ y₁
All you have to do is plug in all of the information above into the formula.
y - 4 = -4/7(x +1)
Answer:
65 degrees
Step-by-step explanation:
An exterior angle form a linear pair with an interior angle.
A linear pair of angles must add up to 180 degrees
180-115 = 65
Answer:
Step-by-step explanation:
20% off...and she saves $13
so 20% of what number is 13
0.20x = 13
x = 13/0.20
x = 65 <== original price
3/4 times n=1
remember that when you multiply 3/4 by 4/3 you get 12/12=1 so it simplifies
remember that you can do anything to an equation as long as you do it to both sides
3/4 ties n=1
multiply both sides by 4/3 to clar fraction
12/12 times n=4/3 times 1
1 times n=4/3
n=4/3
answer is n=4/3 or 1 and 1/3
