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(1) Equation of a Plane  
 
Let P(0,1,0), Q(2,1,3), R(1,-1,2).  
 
(1a) Compute ​PQ​x​PR​. 
(1b) Find the equation of the plane through P, Q and R in the form ax+by+cz=d. 
(1c) What is the angle formed by this plane and the xy-plane? 
 
 
   
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(2) Velocity Vectors  
 
Consider the curve given by the position vector: 
 
(t) < cos(t), sin(t)r = et
et
>  
 
(2a) Find the velocity vector for this trajectory.  
(2b) Find the speed for a particle moving along this trajectory.  
(2c) What is the angle between the position vector and the velocity vector? 
 
   
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(3) Optimization  
 
(x, ) x y x y 6f y = 3 2
+ 2 2
− 6 − 4 + 1  
 
(3a) Find​ , ,
δf
δx
δ f2
δxδx
δ f2
δxδy  
(3b) Find​ , ,
δf
δy
δ f2
δyδy
δ f2
δyδx  
(3d) Classify and determine the relative extrema of the f(x,y). 
   
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(4) LaGrange Multipliers  
 
Minimize the square of the distance from the line x + y = 1 to the point (0,0). 
 
(4a) Let and state gx, gy.(x, )g y = x + y − 1 = 0  
(4b) Let and state fx, fy.(x, )d2
= f y = x2
+ y2
 
(4c) State and solve a system of 3 equations for x,y and .λ  
(4d) What is the minimum value of d? 
 
 
   
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(5) Double Integrals  
 
e dydxM = ∫
1
0
∫
2
2x
4 y2
 
 
(5a) Find the region R over which we are integrating in the xy-plane. 
(5b) Rewrite the given integral in terms of dxdy. 
(5c) Evaluate this new integral to find the mass M of the planar region R. 
   
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(6) Fundamental Theorem of Line Integrals 
 
​F​ = <M,N> = os(x) sin(y), in(x) cos(y)< c s >  
 
(6a) Show that ​F​ is a Conservative Vector Field. 
(6b) Find the Potential Function f(x,y) for the Vector Field ​F​. 
(6c) Evaluate W =​ over the path C:dx dy∫
C
M + N  
ine Segment from (0,− ) to ( , )L π 2
3π
2
π
 
 
 
 
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(7) Green’s Theorem for Work in the Plane 
 
(x, ) < , =< y,F y = M N > x x + y >  
C: CCW once around x2
+ y2
= 1  
<M,N><dx,dy> =W = ∫
C
dx dy∫
C
M + N  
 
(7a) Parametrize the path C in terms of t. 
(7b) Use this parametrization to find the work done. 
 
 
    
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(7) Green’s Theorem for Work in the Plane 
 
(x, ) < , =< y,F y = M N > x x + y >  
C: CCW once around x2
+ y2
= 1  
<M,N><dx,dy> =W = ∫
C
dx dy∫
C
M + N  
 
(7c) Confirm Green’s Theorem for Work. 
 
 
 
 
   
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(8) The Divergence Theorem for Flux in Space 
 
(x, , ) < , , =< z, z, zF y z = P Q R > x y 2 2
>  
S: Bounded by andz = 1 − x2
− y2
z = 0  
lux n dSF = ∫∫
S
F
︿
 
 
(8a) Find the Flux of the vector field F through this closed surface. 
 
   
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(8) The Divergence Theorem for Flux in Space 
 
(x, , ) < , , =< z, z, zF y z = P Q R > x y 2 2
>  
S: Bounded by andz = 1 − x2
− y2
z = 0  
lux n dSF = ∫∫
S
F
︿
 
 
(8b) Confirm the Divergence, aka Gauss-Green, Theorem. 
 
 
   
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(9) Stokes' Theorem for Work in Space 
 
(x, , ) < , , =<− , ,F y z = P Q R > y + z x − z x − y >  
S: andz = 9 − x2
− y2
z ≥ 0  
(9a) Evaluate​ W= dx dy dz∮
C
P + Q + R  
 
   
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(9) Stokes' Theorem for Work in Space 
 
(x, , ) < , , =<− , ,F y z = P Q R > y + z x − z x − y >  
S: andz = 9 − x2
− y2
z ≥ 0  
 
(9b) Verify Stokes’ Theorem. 
   
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TEST5A page: 24

2020 preTEST5A

  • 1.
    MAT225 TEST5A Name: Showall work algebraically if possible. (1) Equation of a Plane     Let P(0,1,0), Q(2,1,3), R(1,-1,2).     (1a) Compute ​PQ​x​PR​.  (1b) Find the equation of the plane through P, Q and R in the form ax+by+cz=d.  (1c) What is the angle formed by this plane and the xy-plane?          TEST5A page: 1
  • 2.
    MAT225 TEST5A Name: Showall work algebraically if possible. TEST5A page: 2
  • 3.
    MAT225 TEST5A Name: Showall work algebraically if possible. (2) Velocity Vectors     Consider the curve given by the position vector:    (t) < cos(t), sin(t)r = et et >     (2a) Find the velocity vector for this trajectory.   (2b) Find the speed for a particle moving along this trajectory.   (2c) What is the angle between the position vector and the velocity vector?        TEST5A page: 3
  • 4.
    MAT225 TEST5A Name: Showall work algebraically if possible.     TEST5A page: 4
  • 5.
    MAT225 TEST5A Name: Showall work algebraically if possible. (3) Optimization     (x, ) x y x y 6f y = 3 2 + 2 2 − 6 − 4 + 1     (3a) Find​ , , δf δx δ f2 δxδx δ f2 δxδy   (3b) Find​ , , δf δy δ f2 δyδy δ f2 δyδx   (3d) Classify and determine the relative extrema of the f(x,y).      TEST5A page: 5
  • 6.
    MAT225 TEST5A Name: Showall work algebraically if possible.     TEST5A page: 6
  • 7.
    MAT225 TEST5A Name: Showall work algebraically if possible. (4) LaGrange Multipliers     Minimize the square of the distance from the line x + y = 1 to the point (0,0).    (4a) Let and state gx, gy.(x, )g y = x + y − 1 = 0   (4b) Let and state fx, fy.(x, )d2 = f y = x2 + y2   (4c) State and solve a system of 3 equations for x,y and .λ   (4d) What is the minimum value of d?          TEST5A page: 7
  • 8.
    MAT225 TEST5A Name: Showall work algebraically if possible.     TEST5A page: 8
  • 9.
    MAT225 TEST5A Name: Showall work algebraically if possible. (5) Double Integrals     e dydxM = ∫ 1 0 ∫ 2 2x 4 y2     (5a) Find the region R over which we are integrating in the xy-plane.  (5b) Rewrite the given integral in terms of dxdy.  (5c) Evaluate this new integral to find the mass M of the planar region R.      TEST5A page: 9
  • 10.
    MAT225 TEST5A Name: Showall work algebraically if possible.     TEST5A page: 10
  • 11.
    MAT225 TEST5A Name: Showall work algebraically if possible. (6) Fundamental Theorem of Line Integrals    ​F​ = <M,N> = os(x) sin(y), in(x) cos(y)< c s >     (6a) Show that ​F​ is a Conservative Vector Field.  (6b) Find the Potential Function f(x,y) for the Vector Field ​F​.  (6c) Evaluate W =​ over the path C:dx dy∫ C M + N   ine Segment from (0,− ) to ( , )L π 2 3π 2 π         TEST5A page: 11
  • 12.
    MAT225 TEST5A Name: Showall work algebraically if possible.     TEST5A page: 12
  • 13.
    MAT225 TEST5A Name: Showall work algebraically if possible. (7) Green’s Theorem for Work in the Plane    (x, ) < , =< y,F y = M N > x x + y >   C: CCW once around x2 + y2 = 1   <M,N><dx,dy> =W = ∫ C dx dy∫ C M + N     (7a) Parametrize the path C in terms of t.  (7b) Use this parametrization to find the work done.           TEST5A page: 13
  • 14.
    MAT225 TEST5A Name: Showall work algebraically if possible.     TEST5A page: 14
  • 15.
    MAT225 TEST5A Name: Showall work algebraically if possible. (7) Green’s Theorem for Work in the Plane    (x, ) < , =< y,F y = M N > x x + y >   C: CCW once around x2 + y2 = 1   <M,N><dx,dy> =W = ∫ C dx dy∫ C M + N     (7c) Confirm Green’s Theorem for Work.              TEST5A page: 15
  • 16.
    MAT225 TEST5A Name: Showall work algebraically if possible.     TEST5A page: 16
  • 17.
    MAT225 TEST5A Name: Showall work algebraically if possible. (8) The Divergence Theorem for Flux in Space    (x, , ) < , , =< z, z, zF y z = P Q R > x y 2 2 >   S: Bounded by andz = 1 − x2 − y2 z = 0   lux n dSF = ∫∫ S F ︿     (8a) Find the Flux of the vector field F through this closed surface.        TEST5A page: 17
  • 18.
    MAT225 TEST5A Name: Showall work algebraically if possible.     TEST5A page: 18
  • 19.
    MAT225 TEST5A Name: Showall work algebraically if possible. (8) The Divergence Theorem for Flux in Space    (x, , ) < , , =< z, z, zF y z = P Q R > x y 2 2 >   S: Bounded by andz = 1 − x2 − y2 z = 0   lux n dSF = ∫∫ S F ︿     (8b) Confirm the Divergence, aka Gauss-Green, Theorem.          TEST5A page: 19
  • 20.
    MAT225 TEST5A Name: Showall work algebraically if possible.       TEST5A page: 20
  • 21.
    MAT225 TEST5A Name: Showall work algebraically if possible. (9) Stokes' Theorem for Work in Space    (x, , ) < , , =<− , ,F y z = P Q R > y + z x − z x − y >   S: andz = 9 − x2 − y2 z ≥ 0   (9a) Evaluate​ W= dx dy dz∮ C P + Q + R         TEST5A page: 21
  • 22.
    MAT225 TEST5A Name: Showall work algebraically if possible.       TEST5A page: 22
  • 23.
    MAT225 TEST5A Name: Showall work algebraically if possible. (9) Stokes' Theorem for Work in Space    (x, , ) < , , =<− , ,F y z = P Q R > y + z x − z x − y >   S: andz = 9 − x2 − y2 z ≥ 0     (9b) Verify Stokes’ Theorem.      TEST5A page: 23
  • 24.
    MAT225 TEST5A Name: Showall work algebraically if possible.   TEST5A page: 24