MyLab Math with Pearson eText -- Standalone Access Card -- for Calculus: Early Transcendentals (3rd Edition)
3rd Edition
ISBN: 9780134856926
Author: William L. Briggs, Lyle Cochran, Bernard Gillett, Eric Schulz
Publisher: PEARSON
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Textbook Question
Chapter 7.3, Problem 71E
Power lines A power line is attached at the same height to two utility poles that are separated by a distance of 100 ft; the power line follows the curve f(x) = a cosh(x/a). Use the following steps to find the value of a that produces a sag of 10 ft midway between the poles. Use a
- a. Show that a satisfies the equation cosh(50/a) − 1 = 10/a.
- b. Let t = 10/a, confirm that the equation in part (a) reduces to cosh 5t − 1 = t, and solve for t using a graphing utility. Report your answer accurate to two decimal places.
- c. Use your answer in part (b) to find a and then compute the length of the power line.
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Chapter 7 Solutions
MyLab Math with Pearson eText -- Standalone Access Card -- for Calculus: Early Transcendentals (3rd Edition)
Ch. 7.1 - What is the domain of ln |x|?Ch. 7.1 - Simplify e ln 2x, ln (e2x), e2 ln x, and ln (2ex)Ch. 7.1 - What is the slope of the curve y = ex at x= ln 2?...Ch. 7.1 - Verify that the derivative and integral results...Ch. 7.1 - Prob. 1ECh. 7.1 - Prob. 2ECh. 7.1 - Evaluate 4xdx.Ch. 7.1 - What is the inverse function of ln x, and what are...Ch. 7.1 - Express 3x, x, and xsin x using the base e.Ch. 7.1 - Evaluate ddx(3x).
Ch. 7.1 - Derivatives Evaluate the following derivatives...Ch. 7.1 - Derivatives with ln x Evaluate the following...Ch. 7.1 - Derivatives with ln x Evaluate the following...Ch. 7.1 - Derivatives with ln x Evaluate the following...Ch. 7.1 - Derivatives with ln x Evaluate the following...Ch. 7.1 - Derivatives with ln x Evaluate the following...Ch. 7.1 - Derivatives Evaluate the derivatives of the...Ch. 7.1 - Derivatives Evaluate the derivatives of the...Ch. 7.1 - Derivatives Evaluate the derivatives of the...Ch. 7.1 - Derivatives Evaluate the derivatives of the...Ch. 7.1 - Derivatives Evaluate the derivatives of the...Ch. 7.1 - Derivatives Evaluate the derivatives of the...Ch. 7.1 - Derivatives Evaluate the derivatives of the...Ch. 7.1 - Derivatives Evaluate the derivatives of the...Ch. 7.1 - Miscellaneous derivatives Compute the following...Ch. 7.1 - Miscellaneous derivatives Compute the following...Ch. 7.1 - Miscellaneous derivatives Compute the following...Ch. 7.1 - Prob. 24ECh. 7.1 - Miscellaneous derivatives Compute the following...Ch. 7.1 - Miscellaneous derivatives Compute the following...Ch. 7.1 - Miscellaneous derivatives Compute the following...Ch. 7.1 - Miscellaneous derivatives Compute the following...Ch. 7.1 - Integrals with ln x Evaluate the following...Ch. 7.1 - Integrals Evaluate the following integrals....Ch. 7.1 - Integrals with ln x Evaluate the following...Ch. 7.1 - Integrals with ln x Evaluate the following...Ch. 7.1 - Integrals with ln x Evaluate the following...Ch. 7.1 - Integrals with ln x Evaluate the following...Ch. 7.1 - Integrals with ln x Evaluate the following...Ch. 7.1 - Integrals with ln x Evaluate the following...Ch. 7.1 - Integrals with ex Evaluate the following...Ch. 7.1 - Integrals with ex Evaluate the following...Ch. 7.1 - Integrals with ex Evaluate the following...Ch. 7.1 - Integrals with ex Evaluate the following...Ch. 7.1 - Integrals with ex Evaluate the following...Ch. 7.1 - Integrals with ex Evaluate the following...Ch. 7.1 - Integrals with general bases Evaluate the...Ch. 7.1 - Integrals with general bases Evaluate the...Ch. 7.1 - Integrals with general bases Evaluate the...Ch. 7.1 - Integrals with general bases Evaluate the...Ch. 7.1 - Integrals with general bases Evaluate the...Ch. 7.1 - Integrals with general bases Evaluate the...Ch. 7.1 - Integrals Evaluate the following integrals....Ch. 7.1 - Miscellaneous integrals Evaluate the following...Ch. 7.1 - Miscellaneous integrals Evaluate the following...Ch. 7.1 - Miscellaneous integrals Evaluate the following...Ch. 7.1 - Miscellaneous integrals Evaluate the following...Ch. 7.1 - Miscellaneous integrals Evaluate the following...Ch. 7.1 - Miscellaneous integrals Evaluate the following...Ch. 7.1 - Miscellaneous integrals Evaluate the following...Ch. 7.1 - Miscellaneous integrals Evaluate the following...Ch. 7.1 - Miscellaneous integrals Evaluate the following...Ch. 7.1 - Miscellaneous integrals Evaluate the following...Ch. 7.1 - Integrals Evaluate the following integrals....Ch. 7.1 - Integrals Evaluate the following integrals....Ch. 7.1 - Miscellaneous integrals Evaluate the following...Ch. 7.1 - Calculator limits Use a calculator to make a table...Ch. 7.1 - Calculator limits Use a calculator to make a table...Ch. 7.1 - Calculator limits Use a calculator to make a table...Ch. 7.1 - Calculator limits Use a calculator to make a table...Ch. 7.1 - Prob. 67ECh. 7.1 - Prob. 68ECh. 7.1 - Prob. 69ECh. 7.1 - Prob. 70ECh. 7.1 - Prob. 71ECh. 7.1 - Prob. 72ECh. 7.1 - Prob. 73ECh. 7.1 - Prob. 74ECh. 7.1 - Prob. 75ECh. 7.1 - Prob. 76ECh. 7.1 - Harmonic sum In Chapter 10, we will encounter the...Ch. 7.1 - Probability as an integral Two points P and Q are...Ch. 7.2 - Population A increases at a constant rate of...Ch. 7.2 - Verify that the time needed for y(t) = y0ekt. to...Ch. 7.2 - Assume y() 100e0.005, 3y (exactly) what...Ch. 7.2 - If a quantity decreases by a factor of 8 every 30...Ch. 7.2 - In terms of relative growth rate, what is the...Ch. 7.2 - Prob. 2ECh. 7.2 - Prob. 3ECh. 7.2 - Prob. 4ECh. 7.2 - Prob. 5ECh. 7.2 - Prob. 6ECh. 7.2 - Suppose a quantity described by the function y(t)...Ch. 7.2 - Suppose a quantity is described by the function...Ch. 7.2 - Give two examples of processes that are modeled by...Ch. 7.2 - Give two examples of processes that are modeled by...Ch. 7.2 - Because of the absence of predators, the number of...Ch. 7.2 - After the introduction of foxes on an island, the...Ch. 7.2 - Absolute and relative growth rates Two functions f...Ch. 7.2 - Absolute and relative growth rates Two functions f...Ch. 7.2 - Designing exponential growth functions Complete...Ch. 7.2 - Designing exponential growth functions Complete...Ch. 7.2 - Designing exponential growth functions Complete...Ch. 7.2 - Designing exponential growth functions Complete...Ch. 7.2 - Designing exponential growth functions Complete...Ch. 7.2 - Designing exponential growth functions Complete...Ch. 7.2 - Determining APY Suppose 1000 is deposited in a...Ch. 7.2 - Tortoise growth In a study conducted at University...Ch. 7.2 - Projection sensitivity According to the 2014...Ch. 7.2 - Energy consumption On the first day of the year (t...Ch. 7.2 - Population of Texas Texas was the third fastest...Ch. 7.2 - Oil consumption Starting in 2018 (t = 0), the rate...Ch. 7.2 - Designing exponential decay functions Devise an...Ch. 7.2 - Designing exponential decay functions Devise an...Ch. 7.2 - Designing exponential decay functions Devise an...Ch. 7.2 - Designing exponential decay functions Devise an...Ch. 7.2 - Population of West Virginia The population of West...Ch. 7.2 - Prob. 32ECh. 7.2 - Atmospheric pressure The pressure of Earths...Ch. 7.2 - Carbon dating The half-life of C-14 is about 5730...Ch. 7.2 - Uranium dating Uranium-238 (U-238) has a half-life...Ch. 7.2 - Radioiodine treatment Roughly 12,000 Americans are...Ch. 7.2 - Caffeine After an individual drinks a beverage...Ch. 7.2 - Caffeine After an individual drinks a beverage...Ch. 7.2 - Prob. 39ECh. 7.2 - Prob. 40ECh. 7.2 - Tumor growth Suppose the cells of a tumor are...Ch. 7.2 - Tripling time A quantity increases according to...Ch. 7.2 - Explain why or why not Determine whether the...Ch. 7.2 - A running model A model for the startup of a...Ch. 7.2 - Prob. 45ECh. 7.2 - Prob. 46ECh. 7.2 - A slowing race Starting at the same time and...Ch. 7.2 - Prob. 48ECh. 7.2 - Compounded inflation The U.S. government reports...Ch. 7.2 - Acceleration, velocity, position Suppose the...Ch. 7.2 - Air resistance (adapted from Putnam Exam, 1939) An...Ch. 7.2 - General relative growth rates Define the relative...Ch. 7.2 - Equivalent growth functions The same exponential...Ch. 7.2 - Geometric means A quantity grows exponentially...Ch. 7.2 - Constant doubling time Prove that the doubling...Ch. 7.3 - Use the definition of the hyperbolic sine to show...Ch. 7.3 - Explain why the graph of tanh x has the horizontal...Ch. 7.3 - Find both the derivative and indefinite integral...Ch. 7.3 - Prob. 4QCCh. 7.3 - Prob. 5QCCh. 7.3 - Prob. 6QCCh. 7.3 - Explain why longer waves travel faster than...Ch. 7.3 - State the definition of the hyperbolic cosine and...Ch. 7.3 - Sketch the graphs of y = cosh x, y sinh x, and y...Ch. 7.3 - What is the fundamental identity for hyperbolic...Ch. 7.3 - Prob. 4ECh. 7.3 - Express sinh1 x in terms of logarithms.Ch. 7.3 - Prob. 6ECh. 7.3 - Prob. 7ECh. 7.3 - On what interval is the formula d/dx (tanh1 x) =...Ch. 7.3 - Prob. 9ECh. 7.3 - Prob. 10ECh. 7.3 - Verifying identities Verify each identity using...Ch. 7.3 - Verifying identities Verify each identity using...Ch. 7.3 - Verifying identities Verify each identity using...Ch. 7.3 - Verifying identities Verify each identity using...Ch. 7.3 - Verifying identities Verify each identity using...Ch. 7.3 - Verifying identities Use the given identity to...Ch. 7.3 - Verifying identities Use the given identity to...Ch. 7.3 - Prob. 18ECh. 7.3 - Derivative formulas Derive the following...Ch. 7.3 - Derivative formulas Derive the following...Ch. 7.3 - Derivative formulas Derive the following...Ch. 7.3 - Derivatives Compute dy/dx for the following...Ch. 7.3 - Derivatives Compute dy/dx for the following...Ch. 7.3 - Derivatives Compute dy/dx for the following...Ch. 7.3 - Derivatives Compute dy/dx for the following...Ch. 7.3 - Derivatives Compute dy/dx for the following...Ch. 7.3 - Derivatives Compute dy/dx for the following...Ch. 7.3 - Derivatives Compute dy/dx for the following...Ch. 7.3 - Derivatives Compute dy/dx for the following...Ch. 7.3 - Prob. 30ECh. 7.3 - Derivatives Find the derivatives of the following...Ch. 7.3 - Derivatives Find the derivatives of the following...Ch. 7.3 - Derivatives Find the derivatives of the following...Ch. 7.3 - Derivatives Find the derivatives of the following...Ch. 7.3 - Prob. 35ECh. 7.3 - Prob. 36ECh. 7.3 - Indefinite integrals Determine each indefinite...Ch. 7.3 - Integrals Evaluate each integral. sech2wtanhwdwCh. 7.3 - Indefinite integrals Determine each indefinite...Ch. 7.3 - Indefinite integrals Determine each indefinite...Ch. 7.3 - Indefinite integrals Determine each indefinite...Ch. 7.3 - Indefinite integrals Determine each indefinite...Ch. 7.3 - Definite integrals Evaluate each definite...Ch. 7.3 - Integrals Evaluate each integral. 0ln2sech2xxdxCh. 7.3 - Definite integrals Evaluate each definite...Ch. 7.3 - Definite integrals Evaluate each definite...Ch. 7.3 - Indefinite integrals Determine the following...Ch. 7.3 - Integrals Evaluate each integral. 48.dxx216,x4Ch. 7.3 - Indefinite integrals Determine the following...Ch. 7.3 - Prob. 50ECh. 7.3 - Indefinite integrals Determine the following...Ch. 7.3 - Prob. 52ECh. 7.3 - Additional integrals Evaluate the following...Ch. 7.3 - Additional integrals Evaluate the following...Ch. 7.3 - Prob. 55ECh. 7.3 - Additional integrals Evaluate the following...Ch. 7.3 - Two ways Evaluate the following integrals two...Ch. 7.3 - Two ways Evaluate the following integrals two...Ch. 7.3 - Visual approximation a. Use a graphing utility to...Ch. 7.3 - Prob. 60ECh. 7.3 - Prob. 61ECh. 7.3 - Points of intersection and area a. Sketch the...Ch. 7.3 - Definite integrals Evaluate the following definite...Ch. 7.3 - Definite integrals Evaluate the following definite...Ch. 7.3 - Definite integrals Evaluate the following definite...Ch. 7.3 - Prob. 66ECh. 7.3 - Prob. 67ECh. 7.3 - Prob. 68ECh. 7.3 - Catenary arch The portion of the curve y=1716coshx...Ch. 7.3 - Length of a catenary Show that the arc length of...Ch. 7.3 - Power lines A power line is attached at the same...Ch. 7.3 - Sag angle Imagine a climber clipping onto the rope...Ch. 7.3 - Wavelength The velocity of a surface wave on the...Ch. 7.3 - Prob. 74ECh. 7.3 - Prob. 75ECh. 7.3 - Prob. 76ECh. 7.3 - Explain why or why not Determine whether the...Ch. 7.3 - Evaluating hyperbolic functions Use a calculator...Ch. 7.3 - Evaluating hyperbolic functions Evaluate each...Ch. 7.3 - Prob. 80ECh. 7.3 - Critical points Find the critical points of the...Ch. 7.3 - Critical points a. Show that the critical points...Ch. 7.3 - Points of inflection Find the x-coordinate of the...Ch. 7.3 - Prob. 84ECh. 7.3 - Area of region Find the area of the region bounded...Ch. 7.3 - Prob. 86ECh. 7.3 - LHpital loophole Explain why lHpitals Rule fails...Ch. 7.3 - Limits Use lHpitals Rule to evaluate the following...Ch. 7.3 - Limits Use lHpitals Rule to evaluate the following...Ch. 7.3 - Prob. 90ECh. 7.3 - Prob. 91ECh. 7.3 - Prob. 92ECh. 7.3 - Kiln design Find the volume interior to the...Ch. 7.3 - Prob. 94ECh. 7.3 - Falling body When an object falling from rest...Ch. 7.3 - Prob. 96ECh. 7.3 - Prob. 97ECh. 7.3 - Prob. 98ECh. 7.3 - Differential equations Hyperbolic functions are...Ch. 7.3 - Prob. 100ECh. 7.3 - Prob. 101ECh. 7.3 - Prob. 102ECh. 7.3 - Prob. 103ECh. 7.3 - Prob. 104ECh. 7.3 - Prob. 105ECh. 7.3 - Theorem 7.8 a. The definition of the inverse...Ch. 7.3 - Prob. 107ECh. 7.3 - Prob. 108ECh. 7.3 - Arc length Use the result of Exercise 108 to find...Ch. 7.3 - Prob. 110ECh. 7.3 - Prob. 111ECh. 7.3 - Definitions of hyperbolic sine and cosine Complete...Ch. 7 - Explain why or why not Determine whether the...Ch. 7 - Integrals Evaluate the following integrals. 56....Ch. 7 - Integrals Evaluate the following integrals. 57....Ch. 7 - Integrals Evaluate the following integrals. 58....Ch. 7 - Integrals Evaluate the following integrals. 59....Ch. 7 - Integrals Evaluate the following integrals. 60....Ch. 7 - Integrals Evaluate the following integrals. 61....Ch. 7 - Integrals Evaluate the following integrals. 62....Ch. 7 - Integrals Evaluate the following integrals. 63....Ch. 7 - Derivatives Find the derivatives of the following...Ch. 7 - Derivatives Find the derivatives of the following...Ch. 7 - Derivatives Find the derivatives of the following...Ch. 7 - Derivatives Find the derivatives of the following...Ch. 7 - Prob. 14RECh. 7 - Prob. 15RECh. 7 - Derivatives Find the derivatives of the following...Ch. 7 - Prob. 17RECh. 7 - Prob. 18RECh. 7 - Prob. 19RECh. 7 - Population growth The population of a large city...Ch. 7 - Caffeine An adult consumes an espresso containing...Ch. 7 - Two cups of coffee A college student consumed two...Ch. 7 - Moores Law In 1965, Gordon Moore observed that the...Ch. 7 - Radioactive decay The mass of radioactive material...Ch. 7 - Population growth Growing from an initial...Ch. 7 - Prob. 26RECh. 7 - Prob. 27RECh. 7 - Curve sketching Use the graphing techniques of...Ch. 7 - Prob. 29RECh. 7 - Prob. 30RECh. 7 - Linear approximation Find the linear approximation...Ch. 7 - Limit Evaluate limx(tanhx)x.Ch. 7 - Derivatives of hyperbolic functions Compute the...Ch. 7 - Arc length Find the arc length of the curve y = ln...
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