Explanation Given Information: The dimensions of a closed-top box are given by length x , width y , and height z (in inches) and the volume of the box is 27 , 000 cubic inches. Formula used: To calculate relative maxima and minima of the function z = f ( x , y ) , (1) Find the partial derivatives ∂ z ∂ x and ∂ z ∂ y . (2) Find the critical points, that is, the point(s) that satisfy ∂ z ∂ x = 0 and ∂ z ∂ y = 0 . (3) Then find all the second partial derivatives and evaluate the value of D at each critical point, where D = ( z x x ) ( z y y ) − ( z x y ) 2 = ∂ 2 z ∂ x 2 ⋅ ∂ 2 z ∂ y 2 − ( ∂ 2 z ∂ x ∂ y ) 2 . (a) If D > 0 , then relative minimum occurs if z x x > 0 and relative maximum occurs if z x x < 0 . (b) If D < 0 , then neither a relative maximum nor a relative minimum occurs. For a function f ( x , y ) , the partial derivative of f with respect to x is calculated by taking the derivative of f ( x , y ) with respect to x and keeping the other variable y constant and the partial derivative of f with respect to y is calculated by taking the derivative of f ( x , y ) with respect to y and keeping the other variable x constant. The partial derivative of f with respect to x is denoted by f x and with respect to y is denoted by f y . For a function z ( x , y ) , the second partial derivative, (1) When both derivatives are taken with respect to x is z x x = ∂ 2 z ∂ x 2 = ∂ ∂ x ( ∂ z ∂ x ) . (2) When both derivatives are taken with respect to y is z y y = ∂ 2 z ∂ y 2 = ∂ ∂ y ( ∂ z ∂ y ) . (3) When first derivative is taken with respect to x and second derivative is taken with respect to y is z x y = ∂ 2 z ∂ y ∂ x = ∂ ∂ y ( ∂ z ∂ x ) . (4) When first derivative is taken with respect to y and second derivative is taken with respect to x is z y x = ∂ 2 z ∂ x ∂ y = ∂ ∂ x ( ∂ z ∂ y ) . Power of x rule for a real number n is such that, if f ( x ) = x n then f ′ ( x ) = n x n − 1 . Quotient rule for function f ( x ) = u ( x ) v ( x ) , where u and v are differentiable functions of x , then f ′ ( x ) = v ( x ) ⋅ u ′ ( x ) − u ( x ) ⋅ v ′ ( x ) ( v ( x ) ) 2 . Constant function rule for a constant c is such that, if f ( x ) = c then f ′ ( x ) = 0 . Coefficient rule for a constant c is such that, if f ( x ) = c ⋅ u ( x ) , where u ( x ) is a differentiable function of x , then f ′ ( x ) = c ⋅ u ′ ( x ) . The surface area of a box with closed top and length l , width w , and height h is A = 2 l h + 2 w h + 2 l w . The volume of a box with length l , width w , and height h is l w h . Calculation: Consider the problem, the dimensions of a closed-top box are given by length x , width y , and height z (in inches) and the volume of the box is 27 , 000 cubic inches. Use the formula for the surface area of a box with closed top and length l , width w , and height h . A = 2 l h + 2 w h + 2 l w . Substitute x for l , y for w , and z for h in A = 2 l h + 2 w h + 2 l w . A = 2 x z + 2 y z + 2 x y Use the formula for the volume of a box with length l , width w , and height h . V = l w h Substitute x for l , y for w , and z for h in V = l w h . V = x y z Since, the volume of the box is 27 , 000 cubic inches. Substitute 27 , 000 for V . 27 , 000 = x y z z = 27 , 000 x y Substitute 27 , 000 x y for z in A = 2 x z + 2 y z + 2 x y . A = 2 x ( 27 , 000 x y ) + 2 y ( 27 , 000 x y ) + 2 x y = 54 , 000 y + 54 , 000 x + 2 x y Thus, the area function is A ( x , y ) = 54 , 000 y + 54 , 000 x + 2 x y . Differentiate A = f ( x , y ) with respect to x by holding y constant, ∂ A ∂ x = ∂ ∂ x ( 54 , 000 y + 54 , 000 x + 2 x y ) = − 54 , 000 x 2 + 2 y Equate the first derivative of function A ( x , y ) = 54 , 000 y + 54 , 000 x + 2 x y with respect to x to zero. − 54 , 000 x 2 + 2 y = 0 2 y = 54 , 000 x 2 y = 27 , 000 x 2 The first partial derivative of function A ( x , y ) = 54 , 000 y + 54 , 000 x + 2 x y with respect to y by holding x constant. ∂ A ∂ y = ∂ ∂ y ( 54 , 000 y + 54 , 000 x + 2 x y ) = − 54 , 000 y 2 + 2 x Equate the first derivative of function A ( x , y ) = 54 , 000 y + 54 , 000 x + 2 x y with respect to y to zero

Mathematical Applications for the Management, Life, and Social Sciences

11th Edition

ISBN: 9781305108042

Author: Ronald J. Harshbarger, James J. Reynolds

Publisher: Cengage Learning

See similar textbooks

Concept explainers

Domain

In simple mathematics terms, a domain is defined as the space on which all the possible inputs for the function will lie. It can also be expressed as a set of departures for the required function.

Videos

Question

Chapter 14.4, Problem 28E

To determine

To calculate: The values of each of the dimensions of a closed-top box of length x, width y, and height z (in inches) if the volume equals 27,000 cubic inches and the box requires the least amount of material to make.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Chapter 14.4, Problem 27E

Chapter 14.4, Problem 29E

Students have asked these similar questions

亚 ח Variables Name avgdr employ educ exerany Label AVG ALCOHOLIC DRINKS PER DAY IN PAST 30 EMPLOYMENT STATUS EDUCATION LEVEL EXERCISE IN PAST 30 DAYS

Numerical ana

Variables Name wage hours IQ KWW educ exper tenure age married black south urban sibs brthord meduc feduc Label monthly earnings average weekly hours IQ score knowledge of world work score years of education years of work experience years with current employer age in years =1 if married =1 if black =1 if live in south =1 if live in SMSA number of siblings birth order mother's education father's education

Chapter 14 Solutions

Mathematical Applications for the Management, Life, and Social Sciences

Ch. 14.1 - CHECKPOINT 1. Find the domain of the function Ch. 14.1 - Prob. 1E Ch. 14.1 - Prob. 2E Ch. 14.1 - Prob. 3E Ch. 14.1 - Prob. 4E Ch. 14.1 - Prob. 5E Ch. 14.1 - Prob. 6E Ch. 14.1 - Prob. 7E Ch. 14.1 - Prob. 8E Ch. 14.1 - Prob. 9E

Ch. 14.1 - Prob. 10E Ch. 14.1 - Prob. 11E Ch. 14.1 - Prob. 12E Ch. 14.1 - Prob. 13E Ch. 14.1 - Prob. 14E Ch. 14.1 - Prob. 15E Ch. 14.1 - Prob. 16E Ch. 14.1 - In Problems 15-22, evaluate each function as...Ch. 14.1 - Prob. 18E Ch. 14.1 - Prob. 19E Ch. 14.1 - Prob. 20E Ch. 14.1 - Prob. 21E Ch. 14.1 - In Problems 15-22, evaluate each function as...Ch. 14.1 - Prob. 23E Ch. 14.1 - Prob. 24E Ch. 14.1 - Prob. 25E Ch. 14.1 - Temperature-humidity models There are different...Ch. 14.1 - Prob. 28E Ch. 14.1 - 29. Mortgage The following tables show that a...Ch. 14.1 - 30. Wind chill Wind and cold temperatures combine...Ch. 14.1 - Prob. 31E Ch. 14.1 - Prob. 32E Ch. 14.1 - Prob. 33E Ch. 14.1 - Prob. 34E Ch. 14.1 - Prob. 35E Ch. 14.1 - 36. Profit The Kirk Kelly Kandy Company makes two...Ch. 14.1 - Prob. 37E Ch. 14.1 - Prob. 38E Ch. 14.2 - Prob. 1CP Ch. 14.2 - Prob. 2CP Ch. 14.2 - Prob. 3CP Ch. 14.2 - Prob. 4CP Ch. 14.2 - Prob. 5CP Ch. 14.2 - Prob. 1E Ch. 14.2 - Prob. 2E Ch. 14.2 - Prob. 3E Ch. 14.2 - Prob. 4E Ch. 14.2 - Prob. 5E Ch. 14.2 - Prob. 6E Ch. 14.2 - Prob. 7E Ch. 14.2 - Prob. 8E Ch. 14.2 - Prob. 9E Ch. 14.2 - Prob. 10E Ch. 14.2 - Prob. 11E Ch. 14.2 - Prob. 12E Ch. 14.2 - Prob. 13E Ch. 14.2 - Prob. 14E Ch. 14.2 - Prob. 15E Ch. 14.2 - Prob. 16E Ch. 14.2 - Prob. 17E Ch. 14.2 - Prob. 18E Ch. 14.2 - 19. Find the slope of the tangent in the...Ch. 14.2 - 20. Find the slope of the tangent in the...Ch. 14.2 - Prob. 21E Ch. 14.2 - Prob. 22E Ch. 14.2 - Prob. 23E Ch. 14.2 - Prob. 24E Ch. 14.2 - Prob. 25E Ch. 14.2 - Prob. 26E Ch. 14.2 - Prob. 27E Ch. 14.2 - Prob. 28E Ch. 14.2 - Prob. 29E Ch. 14.2 - Prob. 30E Ch. 14.2 - Prob. 31E Ch. 14.2 - 32. If , find the following. (a) (b) (c) (d) Ch. 14.2 - 33. If , find the following. Ch. 14.2 - 34. If , find the following. Ch. 14.2 - Prob. 35E Ch. 14.2 - Ch. 14.2 - Ch. 14.2 - Prob. 38E Ch. 14.2 - Prob. 39E Ch. 14.2 - Prob. 40E Ch. 14.2 - 41. . Ch. 14.2 - . Ch. 14.2 - Prob. 43E Ch. 14.2 - Ch. 14.2 - 45. Mortgage When a homeowner has a 25-year...Ch. 14.2 - 46. Mass transportation ridership Suppose that in...Ch. 14.2 - 47. Wilson's lot size formula In economics, the...Ch. 14.2 - 48. Cost Suppose that the total cost (in dollars)...Ch. 14.2 - 49. Pesticide Suppose that the number of thousands...Ch. 14.2 - 50. Profit Suppose that the profit (in dollars)...Ch. 14.2 - Prob. 51E Ch. 14.2 - Prob. 52E Ch. 14.2 - 53. Production Suppose that the output Q (in...Ch. 14.2 - Prob. 54E Ch. 14.2 - Prob. 55E Ch. 14.2 - Prob. 56E Ch. 14.3 - CHECKPOINT If the joint cost in dollars for two...Ch. 14.3 - Prob. 2CP Ch. 14.3 - Prob. 3CP Ch. 14.3 - Prob. 1E Ch. 14.3 - Prob. 2E Ch. 14.3 - 3. The total cost of producing 1 unit of a product...Ch. 14.3 - Prob. 4E Ch. 14.3 - Prob. 5E Ch. 14.3 - Prob. 6E Ch. 14.3 - Prob. 7E Ch. 14.3 - Prob. 8E Ch. 14.3 - 9. If the joint cost function for two products is ...Ch. 14.3 - 10. Suppose the joint cost function for x units of...Ch. 14.3 - 11. Suppose that the joint cost function for two...Ch. 14.3 - Prob. 12E Ch. 14.3 - Prob. 13E Ch. 14.3 - Prob. 14E Ch. 14.3 - Prob. 15E Ch. 14.3 - Prob. 16E Ch. 14.3 - Prob. 17E Ch. 14.3 - Prob. 18E Ch. 14.3 - Prob. 19E Ch. 14.3 - Prob. 20E Ch. 14.3 - 21. Suppose the Cobb-Douglas production function...Ch. 14.3 - Prob. 22E Ch. 14.3 - Prob. 23E Ch. 14.3 - Prob. 24E Ch. 14.3 - Prob. 25E Ch. 14.3 - Prob. 26E Ch. 14.3 - Prob. 27E Ch. 14.3 - Prob. 28E Ch. 14.3 - Prob. 29E Ch. 14.3 - Prob. 30E Ch. 14.4 - CHECKPOINT Suppose that Find Ch. 14.4 - Prob. 2CP Ch. 14.4 - Prob. 3CP Ch. 14.4 - Prob. 4CP Ch. 14.4 - Prob. 1E Ch. 14.4 - Prob. 2E Ch. 14.4 - Prob. 3E Ch. 14.4 - Prob. 4E Ch. 14.4 - Prob. 5E Ch. 14.4 - Prob. 6E Ch. 14.4 - Prob. 7E Ch. 14.4 - Prob. 8E Ch. 14.4 - Prob. 9E Ch. 14.4 - Prob. 10E Ch. 14.4 - Prob. 11E Ch. 14.4 - Prob. 12E Ch. 14.4 - Prob. 13E Ch. 14.4 - Prob. 14E Ch. 14.4 - Prob. 15E Ch. 14.4 - Prob. 16E Ch. 14.4 - Prob. 17E Ch. 14.4 - Prob. 18E Ch. 14.4 - 19. Profit Suppose that the quarterly profit from...Ch. 14.4 - Prob. 20E Ch. 14.4 - 21. Nutrition A new food is designed to add weight...Ch. 14.4 - Prob. 22E Ch. 14.4 - 23. Production Suppose that tons is the...Ch. 14.4 - 24. Production Suppose that x units of one input...Ch. 14.4 - 25. Profit Suppose that a manufacturer produces...Ch. 14.4 - Prob. 26E Ch. 14.4 - Prob. 27E Ch. 14.4 - Prob. 28E Ch. 14.4 - 29. Profit A company manufactures two products, A...Ch. 14.4 - Prob. 30E Ch. 14.4 - Prob. 31E Ch. 14.4 - The manager of the Sea Islands Chicken Shack is...Ch. 14.4 - Prob. 34E Ch. 14.4 - Prob. 35E Ch. 14.4 - Prob. 36E Ch. 14.5 - Prob. 1CP Ch. 14.5 - Prob. 2CP Ch. 14.5 - Prob. 3CP Ch. 14.5 - Prob. 4CP Ch. 14.5 - Prob. 1E Ch. 14.5 - Prob. 2E Ch. 14.5 - Prob. 3E Ch. 14.5 - Prob. 4E Ch. 14.5 - Prob. 5E Ch. 14.5 - Prob. 6E Ch. 14.5 - Prob. 7E Ch. 14.5 - Prob. 8E Ch. 14.5 - Prob. 9E Ch. 14.5 - Prob. 10E Ch. 14.5 - Prob. 11E Ch. 14.5 - Prob. 12E Ch. 14.5 - Prob. 13E Ch. 14.5 - Prob. 14E Ch. 14.5 - Prob. 15E Ch. 14.5 - 16. Utility Suppose that the budget constraint in...Ch. 14.5 - 17. Utility Suppose that the utility function for...Ch. 14.5 - 18. Utility Suppose that the utility function for...Ch. 14.5 - Prob. 19E Ch. 14.5 - Prob. 20E Ch. 14.5 - 21. Cost A firm has two plants, X and Y. Suppose...Ch. 14.5 - Prob. 22E Ch. 14.5 - Prob. 23E Ch. 14.5 - Prob. 24E Ch. 14.5 - 25. Manufacturing Find the dimensions (in...Ch. 14.5 - Prob. 26E Ch. 14 - 1. What is the domain of ? Ch. 14 - Prob. 2RE Ch. 14 - Prob. 3RE Ch. 14 - 4. If . Ch. 14 - Prob. 5RE Ch. 14 - Prob. 6RE Ch. 14 - Prob. 7RE Ch. 14 - Prob. 8RE Ch. 14 - Prob. 9RE Ch. 14 - Prob. 10RE Ch. 14 - Prob. 11RE Ch. 14 - Prob. 12RE Ch. 14 - Prob. 13RE Ch. 14 - Prob. 14RE Ch. 14 - In Problems 15-18, find the second partials. Ch. 14 - Prob. 16RE Ch. 14 - Prob. 17RE Ch. 14 - Prob. 18RE Ch. 14 - Prob. 19RE Ch. 14 - Prob. 20RE Ch. 14 - Prob. 21RE Ch. 14 - Prob. 22RE Ch. 14 - Prob. 23RE Ch. 14 - Prob. 24RE Ch. 14 - Prob. 25RE Ch. 14 - Prob. 26RE Ch. 14 - Prob. 27RE Ch. 14 - Prob. 28RE Ch. 14 - Prob. 29RE Ch. 14 - Prob. 30RE Ch. 14 - Prob. 31RE Ch. 14 - Prob. 32RE Ch. 14 - Prob. 33RE Ch. 14 - Prob. 34RE Ch. 14 - 35. Modeling US. average wage The table gives the...Ch. 14 - Prob. 36RE Ch. 14 - Prob. 1T Ch. 14 - Prob. 2T Ch. 14 - Prob. 3T Ch. 14 - Prob. 4T Ch. 14 - Prob. 5T Ch. 14 - Prob. 6T Ch. 14 - 7. Suppose the demand functions for two products...Ch. 14 - Prob. 8T Ch. 14 - 9. Find x and y that maximize the utility function...Ch. 14 - Prob. 10T

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, subject and related others by exploring similar questions and additional content below.

The values of each of the dimensions of a closed-top box of length x , width y , and height z (in inches) if the volume equals 27 , 000 cubic inches and the box requires the least amount of material to make.

Solution Summary: The author calculates the dimensions of a closed-top box if the volume equals 27,000 cubic inches and the box requires the least amount of material to make.

Concept explainers

Videos

To calculate: The values of each of the dimensions of a closed-top box of length x, width y, and height z (in inches) if the volume equals 27,000 cubic inches and the box requires the least amount of material to make.

Want to see the full answer?

Chapter 14 Solutions