Chapter 14.7, Problem 17E

Find the first and second derivatives of the function. f(u) = √7 3u − 3 f'(u) 2 (7-34) (½) f"(u) = 9 4(7-3u) 32 X Need Help? Read It Watch It SUBMIT ANSWER

11. Consider the 2nd-order non-homogeneous differential equation y′′ − 4y′ + 3y = et + t2What is the complementary (or homogeneous) solution?A. yc = c1e^t + c2t^2 B. yc = c1e^−t + c2e^−3t C. yc = c1e^t + c2e^3t D. yc = c1e^t + c2e^−3t

5. A trial solution for the non-homogeneous equation y′′ + y′ − 2y = e^x isA. Ae^x B. Ae^x+ Be^−2x C. Ae^x + Be^−x D. Axe^x E. None of these.

14. Write u = - sint-cost in the form u = C cos(t - a) with C > 0 and 0 ? PAUSE Z X C VI B N M

19. If the method of undetermined coefficients is used, the form of a particular solution ofy^(4) − y = e^−t + 3 sin(t) isA. yp(t) = Ate^−t + B cos(t) + C sin(t)B. yp(t) = At^2e^−t + B cos(t) + C sin(t)C. yp(t) = Ate^−t + Bt cos(t) + Ct sin(t)D. yp(t) = At^2e^−t + Bt cos(t) + Ct sin(t)E. yp(t) = Ate^−t + Bt sin(t)

15. A spring-mass system is governed by the differential equation 2x′′ + 72x = 100 sin(3ωt) .For what value of ω will resonance occur?A. 3 B. 6√2 C. 2 D. 10 E. No value

Question 3. A manufacturer has modeled its yearly production function P (the value of its entire production, in millions of dollars) as a Cobb-Douglas function P(L, K) = 1.47L0.65 0.35 where L is the number of labor hours (in thousands) and K is the invested capital (in millions of dollars). ӘР Ət (a) Express the rate of change of production 07-2 in time, in terms of the rate of change of the labor force and the rate of change of the capital in time. (b) Suppose that when L = 30 and K = 8, the labor force is decreasing at a rate of 2000 labor hours per year and capital is increasing at a rate of 500,000 per year. What is the rate of change of production per year?

17. Consider a mass-spring system that satisfies 2y′′(t) + by′(t) + 50y(t) = 0.Which of the following is/are true?(i) If b = 0, the motion is critically damped with period π/5 .(ii) If b = 12, the motion is underdamped.(iii) If b = 40, the motion is overdamped.A. (ii) and (iii) only B. (ii) only C. (i) and (ii) only D. (i) and (iii) only E. All

20. Find the general solution to the differential equation y(4) − 8y′′ + 16y = 0A. y = c1e^2x + c2e^−2xB. y = c1xe^2x + c2xe^−2xC. y = c1e^2x + c2e^−2x + c3xe^2x + c4xe^−2xD. y = c1xe^2x + c2xe^−2x + c3x^2e^2x + c4x^2e^−2xE. y = c1 cos 2x + c2 sin 2x + c3x cos 2x + c4x sin 2x