Section 15.1 Worksheet Find the gradient field F = νφ for the potential function φ. Sketch a few level curves of φ and a few vectors of F. φ(x, y)-yx2+ y2 for x2 + y2 2. 9, (x, y) # (0,0) Sectio...
1. Sketch a few of the level curves of the function f(x, y) = surface z = y2 and then use these to graph the f (x, y) 2. Evaluate the following limits if they exist. If they don't, explain why not. (a lim (x,y)(0,0) + 4y2 x4-y4 (b lim (x,y)(0,0) x2 + y2 cos 2 y2) - 1 lim (c (z,y)(0,0 2ry (x, y)(0,0) Is the function f(x, y) continuous at (0,0)? 3 = (х, у) — (0,0) 2x2y...
Let f(x, y) = x(x – 1) + y2. (a) [1 point] Sketch the level curves of f. (b) [2 points] Compute the gradient of f, and sketch it as a vector field. (c) [3 points) Find all critical values of f and classify them as local maxima, local minima, or saddle points.
Question 7 (8 points) Let vf(x,y) denote the gradient field for the function f(x, y) = x2 - y. Sketch a level curve and two gradient field vectors on the level curve.
Consider the following potential function. a. Find the associated gradient field F =Vo. b. Sketch three equipotential curves of Q. c. Show that the vector field F is orthogonal to the equipotential curve at all points (x, y). 5) (12 points) $(x, y) = 2x² + 2y2
Answer All Questions.
(9) Let f(x,y) = 1+ 4- y2. Evaluate f(3,1), find and sketch the domain of f. (10) A thin metal plate, located in the xy-plane, has temperature T(x,y) at the point (x,y). The level curves of T are called isothermals because at all points on such a curve the temperature is the same. Sketch some isothermals if the temperature function is given by 100 T(x, y) = 1 + x2 + 2y2 (11) Show that lim (z2...
8. (b) Sketch the graph of f(x,y) = 1 - x2 - y2. Sketch the level curves of f(x,y,z) = k for f(x,y,z) = 2x - 3y + z-12, with k=0, 24, -12. - 22. 22
3. Sketch the level curves of the function f (, y) = y2 + 2x + y2 - 64 corresponding to the z-values 6 and 6.
1. Sketch the vector field F x, y+(y-x)j F(x, y x, y f 2. Find the gradient vector field of f(r, y)-xe"
1. Sketch the vector field F x, y+(y-x)j F(x, y x, y f 2. Find the gradient vector field of f(r, y)-xe"
2 + (a) Determine and sketch the domain of the function f(x, y) = (x2 + y2 – 4) 9 – (x2 + y2). [7] x6 – yo (b) Evaluate lim (x,y)+(1,1) - Y [5] (c) What does it mean to say that a function f(x, y) has a relative minimum at (a,b)? [4] (d) Find all second order partial derivatives of the function f(x,y) = 22y.
(1 point) Consider the function defined by
?(?,?)=??(9?2+5?2)?2+?2F(x,y)=xy(9x2+5y2)x2+y2
except at (?,?)=(0,0)(x,y)=(0,0) where ?(0,0)=0F(0,0)=0.
Then we have
∂∂?∂?∂?(0,0)=∂∂y∂F∂x(0,0)=
∂∂?∂?∂?(0,0)=∂∂x∂F∂y(0,0)=
Note that the answers are different. The existence and continuity
of all second partials in a region around a point guarantees the
equality of the two mixed second derivatives at the point. In the
above case, continuity fails at (0,0)(0,0).
(1 point) Consider the function defined by F(x, y) = xy(9x2 + 5y2) x2 + y2 except at (x, y) = (0,0)...