Walking on a surface Consider the following surfaces specified in the form z = f ( x, y ) and the oriented curve C in the xy-plane. a. In each case, find z’ ( t ) . b. Imagine that you are walking on the surface directly above the curve C in the direction of positive orientation. Find the values of t for which you are walking uphill ( that is, z is increasing ) . 54. z = 4 x 2 − y 2 + 1 , C : x = cos t , y = sin t ; 0 ≤ t ≤ 2 π
Walking on a surface Consider the following surfaces specified in the form z = f ( x, y ) and the oriented curve C in the xy-plane. a. In each case, find z’ ( t ) . b. Imagine that you are walking on the surface directly above the curve C in the direction of positive orientation. Find the values of t for which you are walking uphill ( that is, z is increasing ) . 54. z = 4 x 2 − y 2 + 1 , C : x = cos t , y = sin t ; 0 ≤ t ≤ 2 π
Solution Summary: The author explains that the value of zprime is -5mathrmsin2t.
Walking on a surfaceConsider the following surfaces specified in the form z = f(x, y) and the oriented curve C in the xy-plane.
a. In each case, find z’ (t).
b. Imagine that you are walking on the surface directly above the curve C in the direction of positive orientation. Find the values of t for which you are walking uphill (that is, z is increasing).
54.
z
=
4
x
2
−
y
2
+
1
,
C
:
x
=
cos
t
,
y
=
sin
t
;
0
≤
t
≤
2
π
2. Consider the following:
Prove that x, x2, and 1/x are the solutions to the homogeneous equation
corresponding to x³y"" + x²y" + 2xy' + 2y = 2x4.
b. use variation of parameters to find a particular solution and complete the general
solution to the differential equation. I am interested in process. You may use a
computer for integration, finding determinants and doing Kramer's.
3. A spring is stretched 6 in. by a mass that weighs 8 lb. The mass is attached to a dashpot
mechanism that has a damping constant of 0.25 lb-sec./ft. and is acted on by an external
force of 4 cos 2t lb.
a. Set-up the differential equation and initial value problem for the system.
b. Write the function in phase-amplitude form.
C.
Determine the transient solution to the system. Show your work.
d. Determine the steady state of this system. Show your work.
e.
Is the system underdamped, overdamped or critically damped? Explain what this
means for the system.
4. Suppose that you have a circuit with a resistance of 20, inductance of 14 H and a
capacitance of 11 F. An EMF with equation of E(t) = 6 cos 4t supplies a continuous charge
60
to the circuit. Suppose that the q(0)= 8 V and the q'(0)=7. Use this information to answer the
following questions
a. Find the function that models the charge of this circuit.
b. Is the circuit underdamped, overdamped or critically damped?
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, calculus and related others by exploring similar questions and additional content below.
Numerical Integration Introduction l Trapezoidal Rule Simpson's 1/3 Rule l Simpson's 3/8 l GATE 2021; Author: GATE Lectures by Dishank;https://www.youtube.com/watch?v=zadUB3NwFtQ;License: Standard YouTube License, CC-BY