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README

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Parametric Equations

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1. Find parametric equations describing the line segment from P(0,0) to Q(7,17).
x=7t and y=17t, where 0 ≤ t ≤ 1
x=7t and y=17t, where 0 ≤ t ≤ 1
2. Find parametric equations describing the line segment from to .
3. Find parametric equations describing the ellipse centered at the origin with major axis of length 6 along the x-axis and the minor axis of length 3 along the y-axis, generated clockwise.

Polar Coordinates

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20. Convert the equation into Cartesian coordinates:
21. Find an equation of the line y=mx+b in polar coordinates.

Sketch the following polar curves without using a computer.

22.
23.
24.

Sketch the following sets of points.

25.
26.

Calculus in Polar Coordinates

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Find points where the following curves have vertical or horizontal tangents.

40.
Horizontal tangents at (2,2) and (2,-2); vertical tangents at (0,0) and (4,0)
Horizontal tangents at (2,2) and (2,-2); vertical tangents at (0,0) and (4,0)
41.
Horizontal tangents at (r,θ) = (4,π/2), (1,7π/6) and (1,-π/6); vertical tangents at (r,θ) = (3,π/6), (3,5π/6), and (0,3π/4)
Horizontal tangents at (r,θ) = (4,π/2), (1,7π/6) and (1,-π/6); vertical tangents at (r,θ) = (3,π/6), (3,5π/6), and (0,3π/4)

Sketch the region and find its area.

42. The region inside the limaçon
9π/2
9π/2
43. The region inside the petals of the rose and outside the circle

Vectors and Dot Product

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60. Find an equation of the sphere with center (1,2,0) passing through the point (3,4,5)
61. Sketch the plane passing through the points (2,0,0), (0,3,0), and (0,0,4)
62. Find the value of if and
63. Find all unit vectors parallel to
64. Prove one of the distributive properties for vectors in :
Failed to parse (unknown function "\begin{eqnarray}"): {\displaystyle \begin{eqnarray} c(\mathbf u + \mathbf v) &=& c(\langle u_1, u_2, u_3\rangle + \langle v_1, v_2, v_3\rangle)\\ &=& c\langle u_1+v_1, u_2+v_2, u_3+v_3\rangle\\ &=& \langle c(u_1+v_1), c(u_2+v_2), c(u_3+v_3)\rangle\\ &=& \langle cu_1+cv_1, cu_2+cv_2, cu_3+cv_3\rangle\\ &=& \langle cu_1, cu_2, cu_3\rangle + \langle cv_1, cv_2, cv_3\rangle\\ &=& c\mathbf u + c\mathbf v. \end{eqnarray}}
Failed to parse (unknown function "\begin{eqnarray}"): {\displaystyle \begin{eqnarray} c(\mathbf u + \mathbf v) &=& c(\langle u_1, u_2, u_3\rangle + \langle v_1, v_2, v_3\rangle)\\ &=& c\langle u_1+v_1, u_2+v_2, u_3+v_3\rangle\\ &=& \langle c(u_1+v_1), c(u_2+v_2), c(u_3+v_3)\rangle\\ &=& \langle cu_1+cv_1, cu_2+cv_2, cu_3+cv_3\rangle\\ &=& \langle cu_1, cu_2, cu_3\rangle + \langle cv_1, cv_2, cv_3\rangle\\ &=& c\mathbf u + c\mathbf v. \end{eqnarray}}
65. Find all unit vectors orthogonal to in
66. Find all unit vectors orthogonal to in
67. Find all unit vectors that make an angle of with the vector

Cross Product

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Find and

80. and
81. and

Find the area of the parallelogram with sides and .

82. and
83. and


84. Find all vectors that satisfy the equation
None
None
85. Find the volume of the parallelepiped with edges given by position vectors , , and
86. A wrench has a pivot at the origin and extends along the x-axis. Find the magnitude and the direction of the torque at the pivot when the force is applied to the wrench n units away from the origin.
, so the torque is directed along
, so the torque is directed along

Prove the following identities or show them false by giving a counterexample.

87.
False:
False:
88.
Once expressed in component form, both sides evaluate to
Once expressed in component form, both sides evaluate to
89.
Failed to parse (unknown function "\begin{eqnarray}"): {\displaystyle \begin{eqnarray}(\mathbf u-\mathbf v)\times(\mathbf u+\mathbf v)&=&(\mathbf u-\mathbf v)\times\mathbf u + (\mathbf u-\mathbf v)\times\mathbf v\\&=&\mathbf u\times\mathbf u - \mathbf v\times\mathbf u + \mathbf u\times\mathbf v - \mathbf v\times\mathbf v\\&=&\mathbf u\times\mathbf v-\mathbf v\times\mathbf u\\&=&\mathbf u\times\mathbf v + \mathbf u \times \mathbf v\\&=&2(\mathbf u\times\mathbf v)\end{eqnarray}}
Failed to parse (unknown function "\begin{eqnarray}"): {\displaystyle \begin{eqnarray}(\mathbf u-\mathbf v)\times(\mathbf u+\mathbf v)&=&(\mathbf u-\mathbf v)\times\mathbf u + (\mathbf u-\mathbf v)\times\mathbf v\\&=&\mathbf u\times\mathbf u - \mathbf v\times\mathbf u + \mathbf u\times\mathbf v - \mathbf v\times\mathbf v\\&=&\mathbf u\times\mathbf v-\mathbf v\times\mathbf u\\&=&\mathbf u\times\mathbf v + \mathbf u \times \mathbf v\\&=&2(\mathbf u\times\mathbf v)\end{eqnarray}}

Calculus of Vector-Valued Functions

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100. Differentiate .
101. Find a tangent vector for the curve at the point .
102. Find the unit tangent vector for the curve .
103. Find the unit tangent vector for the curve at the point .
104. Find if and .
105. Evaluate

Motion in Space

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120. Find velocity, speed, and acceleration of an object if the position is given by .
, ,
, ,
121. Find the velocity and the position vectors for if the acceleration is given by .
,
,

Length of Curves

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Find the length of the following curves.

140.
141.

Parametrization and Normal Vectors

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142. Find a description of the curve that uses arc length as a parameter:
143. Find the unit tangent vector T and the principal unit normal vector N for the curve Check that TN=0.

Equations of Lines And Planes

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160. Find an equation of a plane passing through points
161. Find an equation of a plane parallel to the plane 2xy+z=1 passing through the point (0,2,-2)
162. Find an equation of the line perpendicular to the plane x+y+2z=4 passing through the point (5,5,5).
163. Find an equation of the line where planes x+2yz=1 and x+y+z=1 intersect.
164. Find the angle between the planes x+2yz=1 and x+y+z=1.
165. Find the distance from the point (3,4,5) to the plane x+y+z=1.

Limits And Continuity

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Evaluate the following limits.

180.
−2
−2
181.
1/6
1/6

At what points is the function f continuous?

182.
183.
All points (x,y) except for (0,0) and the line y=x+1
All points (x,y) except for (0,0) and the line y=x+1

Use the two-path test to show that the following limits do not exist. (A path does not have to be a straight line.)

184.
The limit is 1 along the line y=x, and −1 along the line y=−x
The limit is 1 along the line y=x, and −1 along the line y=−x
185.
The limit is 0 along the line y=0, and along the line x=2y
The limit is 0 along the line y=0, and along the line x=2y
186.
The limit is 1 along the line y=0, and −1 along the line x=0
The limit is 1 along the line y=0, and −1 along the line x=0
187.
The limit is 0 along any line of the form y=mx, and 2 along the parabola
The limit is 0 along any line of the form y=mx, and 2 along the parabola

Partial Derivatives

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200. Find if
201. Find all three partial derivatives of the function

Find the four second partial derivatives of the following functions.

202.
203.

Chain Rule

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Find

220.
221.
0
0
222.
0
0

Find

223.
Failed to parse (syntax error): {\displaystyle f_s = \cos(s+t)\cos(2s-2t) - 2\sin(s+t)\sin(2s-2t)\\ f_t = \cos(s+t)\cos(2s-2t) + 2\sin(s+t)\sin(2s-2t)}
Failed to parse (syntax error): {\displaystyle f_s = \cos(s+t)\cos(2s-2t) - 2\sin(s+t)\sin(2s-2t)\\ f_t = \cos(s+t)\cos(2s-2t) + 2\sin(s+t)\sin(2s-2t)}
224.
Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "http://localhost:6011/en.wikibooks.org/v1/":): {\displaystyle \displaystyle f_s = \frac{-2t(t+1)}{(st+s-t)^2}\\ \displaystyle f_t = \frac{2s}{(st+s-t)^2}}
Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "http://localhost:6011/en.wikibooks.org/v1/":): {\displaystyle \displaystyle f_s = \frac{-2t(t+1)}{(st+s-t)^2}\\ \displaystyle f_t = \frac{2s}{(st+s-t)^2}}


225. The volume of a pyramid with a square base is , where x is the side of the square base and h is the height of the pyramid. Suppose that and for Find

Tangent Planes

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Find an equation of a plane tangent to the given surface at the given point(s).

240.
241.
242.
243.

Maximum And Minimum Problems

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Find critical points of the function f. When possible, determine whether each critical point corresponds to a local maximum, a local minimum, or a saddle point.

260.
Local minima at (1,1) and (−1,−1), saddle at (0,0)
Local minima at (1,1) and (−1,−1), saddle at (0,0)
261.
Saddle at (0,0)
Saddle at (0,0)
262.
Saddle at (0,0), local maxima at local minima at
Saddle at (0,0), local maxima at local minima at

Find absolute maximum and minimum values of the function f on the set R.

263.
Maximum of 9 at (0,−2) and minimum of 0 at (0,1)
Maximum of 9 at (0,−2) and minimum of 0 at (0,1)
264. R is a closed triangle with vertices (0,0), (2,0), and (0,2).
Maximum of 0 at (2,0), (0,2), and (0,0); minimum of −2 at (1,1)
Maximum of 0 at (2,0), (0,2), and (0,0); minimum of −2 at (1,1)


265. Find the point on the plane xy+z=2 closest to the point (1,1,1).
266. Find the point on the surface closest to the plane

Double Integrals over Rectangular Regions

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Evaluate the given integral over the region R.

280.
281.
282.

Evaluate the given iterated integrals.

283.
284.

Double Integrals over General Regions

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Evaluate the following integrals.

300. R is bounded by x=0, y=2x+1, and y=5−2x.
301. R is in the first quadrant and bounded by x=0, and

Use double integrals to compute the volume of the given region.

302. The solid in the first octant bound by the coordinate planes and the surface
303. The solid beneath the cylinder and above the region
304. The solid bounded by the paraboloids and

Double Integrals in Polar Coordinates

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320. Evaluate for
321. Find the average value of the function over the region
322. Evaluate
323. Evaluate if R is the unit disk centered at the origin.

Triple Integrals

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340. Evaluate

In the following exercises, sketching the region of integration may be helpful.

341. Find the volume of the solid in the first octant bounded by the plane 2x+3y+6z=12 and the coordinate planes.
342. Find the volume of the solid in the first octant bounded by the cylinder for , and the planes y=x and x=0.
343. Evaluate
344. Rewrite the integral in the order dydzdx.

Cylindrical And Spherical Coordinates

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360. Evaluate the integral in cylindrical coordinates:
361. Find the mass of the solid cylinder given the density function
362. Use a triple integral to find the volume of the region bounded by the plane z=0 and the hyperboloid
363. If D is a unit ball, use a triple integral in spherical coordinates to evaluate
364. Find the mass of a solid cone if the density function is
365. Find the volume of the region common to two cylinders:

Center of Mass and Centroid

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380. Find the center of mass for three particles located in space at (1,2,3), (0,0,1), and (1,1,0), with masses 2, 1, and 1 respectively.
381. Find the center of mass for a piece of wire with the density for
382. Find the center of mass for a piece of wire with the density for
383. Find the centroid of the region in the first quadrant bounded by the coordinate axes and
384. Find the centroid of the region in the first quadrant bounded by , , and .
385. Find the center of mass for the region , with the density
386. Find the center of mass for the triangular plate with vertices (0,0), (0,4), and (4,0), with density

Vector Fields

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One can sketch two-dimensional vector fields by plotting vector values, flow curves, and/or equipotential curves.

401. Find and sketch the gradient field for the potential function .
402. Find and sketch the gradient field for the potential function for and .
403. Find the gradient field for the potential function

Line Integrals

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420. Evaluate if C is the line segment from (0,0) to (5,5)
421. Evaluate if C is the circle of radius 4 centered at the origin
422. Evaluate if C is the helix
423. Evaluate if and C is the arc of the parabola
424. Find the work required to move an object from (1,1,1) to (8,4,2) along a straight line in the force field

Conservative Vector Fields

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Determine if the following vector fields are conservative on

440.
No
No
441.
Yes
Yes

Determine if the following vector fields are conservative on their respective domains in When possible, find the potential function.

442.
443.

Green's Theorem

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460. Evaluate the circulation of the field over the boundary of the region above y=0 and below y=x(2-x) in two different ways, and compare the answers.
461. Evaluate the circulation of the field over the unit circle centered at the origin in two different ways, and compare the answers.
462. Evaluate the flux of the field over the square with vertices (0,0), (1,0), (1,1), and (0,1) in two different ways, and compare the answers.

Divergence And Curl

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480. Find the divergence of
481. Find the divergence of
482. Find the curl of
483. Find the curl of
484. Prove that the general rotation field , where is a non-zero constant vector and , has zero divergence, and the curl of is .
If , then

, and then

If , then

, and then

Surface Integrals

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500. Give a parametric description of the plane
501. Give a parametric description of the hyperboloid
502. Integrate over the portion of the plane z=2−xy in the first octant.
503. Integrate over the paraboloid
504. Find the flux of the field across the surface of the cone
with normal vectors pointing in the positive z direction.
505. Find the flux of the field across the surface
with normal vectors pointing in the positive y direction.

Stokes' Theorem

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520. Use a surface integral to evaluate the circulation of the field on the boundary of the plane in the first octant.
521. Use a surface integral to evaluate the circulation of the field on the circle
522. Use a line integral to find
where , is the upper half of the ellipsoid , and points in the direction of the z-axis.
523. Use a line integral to find
where , is the part of the sphere for , and points in the direction of the z-axis.

Divergence Theorem

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Compute the net outward flux of the given field across the given surface.

540. , is a sphere of radius centered at the origin.
541. , is the boundary of the tetrahedron in the first octant bounded by
542. , is the boundary of the cube
543. , is the surface of the region bounded by the paraboloid and the xy-plane.
544. , is the boundary of the region between the concentric spheres of radii 2 and 4, centered at the origin.
545. , is the boundary of the region between the cylinders and and cut off by planes and