





Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
These are the notes of Past Paper of Multivariable Calculus. Key important points are: Vector Algebra, Constant Force, Work Done by Force, Area of Parallelogram, Vector Projection, Orthogonal Projection, Parametric Curve, Parametric Equation, Point of Intersection
Typology: Exams
1 / 9
This page cannot be seen from the preview
Don't miss anything!






This exam contains 6 problems, worth a total of 100 points. Only work submitted on this booklet will be considered. Please write the answers in the corresponding boxes. SHOW YOUR WORK.
This page intentionally left blank
Problem 2. (5+5= 10 points) Throughout this problem ~v = ใ 1 , โ 2 , 3 ใ and P = (2, โ 1 , 4).
(a) If Q = (5, โ 2 , 1), find the vector projection of P Q~ onto ~v.
Answer: (b)proj~v P Q~ =
(b) Let ` denote the line through P parallel to ~v, and consider the point Q = (5, โ 2 , 1).
Find the point R on such that RQ~ is perpendicular to ~v. (R is the orthogonal projection of Q onto.) Hint: Draw a figure; you may want to use part (b).
Answer: (c) R =
Problem 3. (7+8+5=20 points) Consider the parametric curve
~r(t) = ใt , t^2 , t^3 ใ
(a) Find the parametric equation ~q(s) of the tangent line to the curve at a time t = T.
Answer: (a) ~q(s) =
(b) If T = 2, find the point of intersection of the tangent line of part (a) with the xy plane.
Answer: (b)
(c) Set up an explicit definite integral equal to the length of the arc of the curve from the origin to the point (2, 4 , 8). You do not have to evaluate the integral. Circle your answer.
Problem 5. (5+5+10=20 points) Throughout this problem
f (x, y, z) = cos(xy) + z^2
(a) Compute โf at an arbitrary point (x, y, z).
Answer: (a)
(b) Find the directional derivative of f at (1, ฯ/ 2 , 1) in the direction of the vector 4~ฤฑ โ 3 ~k.
Answer: (b)
(c) Find the equation of the plane tangent to the surface cos(xy) + z^2 = 1 at the point (1, ฯ/ 2 , 1).
Answer: (c)
Problem 6. (5x4=20 points) On the following page you will find five plots. Assume that the scales of the x and y axes are the same. You are also given the following statements about plots: (1) This plot represents the graph of the function f 1 (x, y) =
x^2 + y^2. (2) This is a contour plot of the function f 1 (x, y) =
x^2 + y^2. (3) These are curves with equations sin(x^2 + y^2 ) = c, for several evenly-spaced values of the constant c. (4) This is a portion of the graph of the function f 2 (x, y) = sin(x^2 + y^2 ). (5) This is part of the image of the parametric surface ~r(s, t) = (s, t, sin(s^2 + t^2 )). (6) These are some level curves of the function f 3 (x, y) = x^2 + 2y^2. (7) This is a portion of the graph of the function f 4 (x, y) = (x^2 โ y^2 )/(1 + x^2 ) (8) This represents a level surface of the function g(x, y, z) = z โ (x^2 โ y^2 )/(1 + x^2 ). (9) These are some level curves of the function f 4 (x, y) = (x^2 โ y^2 )/(1 + x^2 ) (10) This is a portion of the graph of the function f 5 (x, y) = x + y(1 โ y). (11) These are some level curves of the function f 5 (x, y) = x + y(1 โ y). (12) This is a portion of the graph of the function f 6 (x, y) = 2 cos(2x)^2 + y^2. (13) These are some level curves of the function f 6 (x, y) = 2 cos(2x)^2 + y^2.
Fill in the following table with the numbers of the above statements that apply to each plot.
Note: Not all statements apply to some plot, and some plots may have more than one statement that applies to them.
Plot No. Statements that apply 1 2 3 4 5