What expression can be used for estimating 868 divided by 28

The base of an aquarium with given volume V is made of slate and the sides are made of glass. If the slate costs seven times as

Olin [163]

Answer:

x = ∛(2V/7)

y = ∛(2V/7)

z = 3.5 [∛(2V/7)]

{x,y,z} = { ∛(2V/7), ∛(2V/7), 3.5[∛(2V/7)] }

Step-by-step explanation:

The aquarium is a cuboid open at the top.

Let the dimensions of the base of the aquarium be x and y.

The height of the aquarium is then z.

The volume of the aquarium is then

V = xyz

Area of the base of the aquarium = xy

Area of the other faces = 2xz + 2yz

The problem is to now minimize the value of the cost function.

The cost of the area of the base per area is seven times the cost of any other face per area.

With the right assumption that the cost of the other faces per area is 1 currency units, then, the cost of the base of the aquarium per area would then be 7 currency units.

Cost of the base of the aquarium = 7xy

cost of the other faces = 2xz + 2yz

Total cost function = 7xy + 2xz + 2yz

C(x,y,z) = 7xy + 2xz + 2yz

We're to minimize this function subject to the constraint that

xyz = V

The constraint can be rewritten as

xyz - V = 0

Using Lagrange multiplier, we then write the equation in Lagrange form

Lagrange function = Function - λ(constraint)

where λ = Lagrange factor, which can be a function of x, y and z

L(x,y,z) = 7xy + 2xz + 2yz - λ(xyz - V)

We then take the partial derivatives of the Lagrange function with respect to x, y, z and λ. Because these are turning points and at the turning point, each of the partial derivatives is equal to 0.

(∂L/∂x) = 7y + 2z - λyz = 0

λ = (7y + 2z)/yz = (7/z) + (2/y) (eqn 1)

(∂L/∂y) = 7x + 2z - λxz = 0

λ = (7x + 2z)/xz = (7/z) + (2/x) (eqn 2)

(∂L/∂z) = 2x + 2y - λxy = 0

λ = (2x + 2y)/xy = (2/y) + (2/x) (eqn 3)

(∂L/∂λ) = xyz - V = 0

We can then equate the values of λ from the first 3 partial derivatives and solve for the values of x, y and z

(eqn 1) = (eqn 2)

(7/z) + (2/y) = (7/z) + (2/x)

(2/y) = (2/x)

y = x

Also,

(eqn 1) = (eqn 3)

(7/z) + (2/x) = (2/y) + (2/x)

(7/z) = (2/y)

z = (7y/2)

Hence, at the point where the box has minimal area,

y = x,

z = (7y/2) = (7x/2)

We can then substitute those into the constraint equation for y and z

xyz = V

x(x)(7x/2) = V

(7x³/2) = V

x³ = (2V/7)

x = ∛(2V/7)

y = x = ∛(2V/7)

z = (7x/2) = 3.5 [∛(2V/7)]

The values of x, y and z in terms of the volume that minimizes the cost function are

{x,y,z} = {∛(2V/7), ∛(2V/7), 3.5[∛(2V/7)]}

Hope this Helps!!!

7 0

3 years ago

Woodland Bicycles makes two models of off-road bicycles: the Explorer, which sells for $250, and the Grande Expedition, which se

elena-s [515]

Answer:

Step-by-step explanation:

Let X be number of woodland bicyles and Y grande expedition

Our objective is to maximize profit

Z = 250x+350Y

Constraints are: 2x+3y<450 and

x+y<375

(given)

Solution gives negative y. Hence intersecting point is not within constraint.

So choices satisfying the constraints would be min of 225, 375 for x and min of 150,375 for x

i.e x=225 and y =150

To maximize revenue 225 Woodland and 150 Grande to be produced

4 0

3 years ago

Read 2 more answers

Find the derivative of y= 1 / x

givi [52]

Answer:

dy/dx = -1/ $x^{2}$

Step-by-step explanation:

y = 1/x

dy/dx = d/dx(1/x)

=> dy/dx = d/dx( $x^{-1}$ )

=> dy/dx = - $x^{-2}$

=> dy/dx = -1/ $x^{2}$

6 0

3 years ago

Plz help with this math. Can't find the area of the triangular faces.

Zina [86]

First of all, you have to find the area of both triangles:
$\frac{bh}{2}$
$\frac{4*4}{2}$
Or just 16 because there are 2 of the same triangles.

Now you have to find the area of the 3 rectangles.

The two that are in the front are 4*3 (l*h) or 12*2 (because there are 2 congruent rectangles. The area of those rectangles is 24 square mm.

Now you find the area of the back rectangle:
5.7*3 = 17.1

Finally, you add all the found numbers to figure out the surface area.
17.1 + 16 + 24 = 57.1 square millimeters.

Hope this helped,
Loafly

4 0

3 years ago

X+4y=4 in slope intercept form

MAXImum [283]

Answer:

Slope: −14y-intercept: (0,1)

Step-by-step explanation:

7 0

3 years ago