Let z = f (x, y) be a differentiable function on which it is known that the maximum directional derivative of z at a point P gives 5. Consider the following statements: I. The gradient vector of z in P is necessarily (4, 3) or (−4, −3). II. There is no vector u ∈ R2 such that Duz (P) = −7. III. If it is known that ∂z/∂x (P) = 3, then necessarily ∂z/∂y (P) = 4 or ∂z/∂y (P) = −4. Of the above statements are TRUE: A) II and III B) I and II C) Just II D) Just III

Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
icon
Related questions
Question

Let z = f (x, y) be a differentiable function on which it is known that the maximum directional derivative of z at a point P gives 5. Consider the following statements:

I. The gradient vector of z in P is necessarily (4, 3) or (−4, −3).
II. There is no vector u ∈ R2 such that Duz (P) = −7.
III. If it is known that ∂z/∂x (P) = 3, then necessarily ∂z/∂y (P) = 4 or ∂z/∂y (P) = −4.

Of the above statements are TRUE:

A) II and III

B) I and II

C) Just II

D) Just III

Expert Solution
steps

Step by step

Solved in 2 steps with 1 images

Blurred answer
Similar questions
Recommended textbooks for you
Advanced Engineering Mathematics
Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated
Numerical Methods for Engineers
Numerical Methods for Engineers
Advanced Math
ISBN:
9780073397924
Author:
Steven C. Chapra Dr., Raymond P. Canale
Publisher:
McGraw-Hill Education
Introductory Mathematics for Engineering Applicat…
Introductory Mathematics for Engineering Applicat…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY
Mathematics For Machine Technology
Mathematics For Machine Technology
Advanced Math
ISBN:
9781337798310
Author:
Peterson, John.
Publisher:
Cengage Learning,
Basic Technical Mathematics
Basic Technical Mathematics
Advanced Math
ISBN:
9780134437705
Author:
Washington
Publisher:
PEARSON
Topology
Topology
Advanced Math
ISBN:
9780134689517
Author:
Munkres, James R.
Publisher:
Pearson,