Calculus homework
QUESTION 1
1. Find the particular solution determined by the given condition. f'(x) = 3x2 - 2x; f(0) = 18
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f(x) = 3x3 + 2x2 + 18 |
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f(x) = 3x3 + x2 + 18 |
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f(x) = x3 - x2 + 18 |
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f(x) = x3 + 2x2 + 18 |
5 points
QUESTION 2
1. Find the general solution for the differential equation. y ' = 2e3x
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2e3x + C |
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6e3x + C |
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5 points
QUESTION 3
1. Solve the problem.
If a population is changed by either immigration or emigration, a model for the population is
where y is the population at time t and f(t) is some function of t that describes the net effect of the emigration/immigration. Assume that k = 0.02 and y(0) = 10,000. Solve this differential equation for y, given that
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y = 100t + 5000 + 5000e-0.02t |
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y = 100t + 5000 + 5000e0.02t |
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y = -100t + 5000 + 5000e-0.02t |
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y = -100t - 5000 + 5000e0.02t |
5 points
QUESTION 4
1. Solve the problem.
The logistic differential equation
= 0.08P(300 - P)
describes the growth of a population P, where t is measured in years.
Find the limiting population.
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600 |
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150 |
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2.4 |
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300 |
5 points
QUESTION 5
1. Solve the problem.
If a population is changed by either immigration or emigration, a model for the population is
where y is the population at time t and f(t) is some function of t that describes the net effect of the emigration/immigration. Assume that k = 0.02 and y(0) = 10,000. Solve this differential equation for y, given that
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y = 1100t - 55,000 + 65,000e-0.02t |
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y = -1100t - 55,000 + 65,000e0.02t |
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y = 1100t + 55,000 + 65,000e-0.02t |
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y = -1100t - 55,000 + 65,000e-0.02t |
5 points
QUESTION 6
1. Solve.
= 8x7y
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y = Cex8 |
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y = 8Cx7ex7 |
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y = 8Cx8ex7 |
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y = 8Cx8ex8 |
5 points
QUESTION 7
1. Solve.
=
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y = ± |
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y = |
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y = |
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y = ± |
5 points
QUESTION 8
1. Find the general solution of the differential equation, or the particular solution if an initial condition is given. 5y' - 10xy - x = 0
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y = |
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y = - |
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y = - |
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y = - |
5 points
QUESTION 9
1. Find the general solution of the differential equation, or the particular solution if an initial condition is given. y' + 2y = 21
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y = |
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y = 21 + Ce2x |
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y = |
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y = |
5 points
1. Solve the problem.
The logistic differential equation
= 0.07P(700 - P)
describes the growth of a population P, where t is measured in years.
Find the limiting population.
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700 |
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4.9 |
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350 |
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1400 |
5 points
QUESTION 11
1. Find the particular solution determined by the given condition. y' = 4x + 10; y = -21 when x = 0
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y = 2x2 + 10x - 10.5 |
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y = 4x2 + 10x - 10.5 |
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y = 2x2 + 10x - 21 |
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y = 4x2 + 10x - 21 |
5 points
QUESTION 12
1. Find the general solution for the differential equation. y ' = 18x2
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x3 + C |
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6x3 + C |
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18x3 + C |
5 points
QUESTION 13
1. Solve the problem.
The growth rate of a certain stock is modeled by where V = the value of the stock, per share, after time t (in months), and k = a constant. Find the solution to the differential equation in terms of t and k.
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V = 39 - 39e-kt |
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V = 29 - 10e-kt |
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V = 39 - 10ekt |
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V = 39 - 10e-kt |
5 points
QUESTION 14
1. Find the general solution of the differential equation, or the particular solution if an initial condition is given. y' + 3y = 12
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y = 4 + Ce-12x |
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y = 4 + Ce-3x |
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y = |
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y = 12 + Ce-3x |
5 points
QUESTION 15
1. Find the general solution of the differential equation, or the particular solution if an initial condition is given. y' + 2xy = 21x
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y = |
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y = 21 + Cex2 |
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y = |
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y = |
5 points
QUESTION 16
1. Find the general solution for the differential equation. y ' = x - 16
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2x2 - 16 + C |
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x3 - 16x + C |
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5 points
QUESTION 17
1. Solve the problem.
Find the demand function q = D(x), given that E(x) = and q = e when x = 8.
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q = e8/x |
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q = 8 lnx |
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q = ln |
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q = |
5 points
QUESTION 18
1. Find the general solution for the differential equation. y ' = 72x2 - 20x
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72x3 - 10x2 + C |
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72x3 - 20x2 + C |
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24x3 - 20x2 + C |
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24x3 - 10x2 + C |
5 points
QUESTION 19
1. Find the particular solution determined by the given condition.
y' = ; y = 21 when x = 1
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y = 5 ln x + 21 |
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y = ln x + 21 |
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y = ln x + 19 |
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y = 5 ln x + 2.5 |
5 points
QUESTION 20
1. Solve.
3y2 = 7x
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y = - |
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y = |
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y = - |
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y = |
5 points