Answer:
400 m^2.
Step-by-step explanation:
The largest area is obtained where the enclosure is a square.
I think that's the right answer because a square is a special form of a rectangle.
So the square would be 20 * 20 = 400 m^2.
Proof:
Let the sides of the rectangle be x and y m long
The area A = xy.
Also the perimeter 2x + 2y = 80
x + y = 40
y = 40 - x.
So substituting for y in A = xy:-
A = x(40 - x)
A = 40x - x^2
For maximum value of A we find the derivative and equate it to 0:
derivative A' = 40 - 2x = 0
2x = 40
x = 20.
So y = 40 - x
= 40 - 20
=20
x and y are the same value so x = y.
Therefore for maximum area the rectangle is a square.
To find the average rate of change in a interval
We use the following formula:
Applying this to our interval
We have the following rate of change:
We have an average rate of change equals to 6.
Answer:
207 cubic centimeters
Step-by-step explanation:
Given
volume of cone = 9 cubic centimeters
Since the cone and cylinder above have the same radius, r, and height, h, then r = h
volume of the cone = 1/3πr²h
69 = 1/3πr²h
πr²h = 69*3
πr²h = 207cubic cm
Since the volume of the cylinder = πr²h
Hence volume of the cylinder is 207 cubic centimeters
