Exam 11: Partial Derivatives

arrow
  • Select Tags
search iconSearch Question
  • Select Tags

Compute the minimum value of f(x,y,z)=x2+y+z2f ( x , y , z ) = x ^ { 2 } + y + z ^ { 2 } subject to the condition that g(x)=2x+y+4z=6g ( x ) = 2 x + y + 4 z = 6 .

(Essay)
4.8/5
(41)

Let f(x,y,z)=xyzf ( x , y , z ) = x ^ { y z } , x>0x > 0 . Find the value of the partial derivative fz(2,3,0)f _ { z } ( 2,3,0 ) .

(Multiple Choice)
4.8/5
(36)

Find the local maximum and minimum values and saddle points of the function f(x,y)=3x3+y29x+4yf ( x , y ) = 3 x ^ { 3 } + y ^ { 2 } - 9 x + 4 y .

(Essay)
4.9/5
(33)

Find the local maximum and minimum values and saddle points of the function f(x,y)=x4+4xy2y2+1f ( x , y ) = - x ^ { 4 } + 4 x y - 2 y ^ { 2 } + 1 .

(Essay)
4.8/5
(40)

Find the domain of the function f(x,y)=xy2f ( x , y ) = \sqrt { x - y ^ { 2 } } .

(Multiple Choice)
4.8/5
(41)

Suppose that the equation F(x,y,z)=0F ( x , y , z ) = 0 defines ZZ implicitly as a function of xx and yy . Let (a,b,c)( a , b , c ) be a point such that F(a,b,c)=0F ( a , b , c ) = 0 and F(a,b,c)=(2,3,4)\nabla F ( a , b , c ) = ( 2 , - 3,4 ) . Find δzδx(a,b)\frac { \delta z } { \delta x } ( a , b ) and δzδy(a,b)\frac { \delta z } { \delta y } ( a , b ) .

(Essay)
4.8/5
(32)

Find an equation of the tangent plant to the parametric surface x=u,y=v,z=u2+vx = u , y = v , z = u ^ { 2 } + v at the point (1,2,3)( 1,2,3 ) .

(Multiple Choice)
4.8/5
(33)

The radius of a right circular cylinder is increasing at a rate of 2 cm/min and its height is decreasing at 4cm/min. At what rate is the volume changing at the instant when the radius is 4 cm and the height is 10 cm?

(Essay)
4.9/5
(33)

Suppose the point (2,3)( 2,3 ) is on a curve CC which is a level curve of the surface z=x2+2yz = x ^ { 2 } + 2 y . Can it be concluded that the point (4,3)( 4 , - 3 ) is also on CC ? Explain.

(Essay)
4.8/5
(30)

Evaluate lim(x,yz)(1,0,2)xy+z\lim _ { ( x , y z ) \rightarrow ( 1,0 , - 2 ) } \frac { x } { y + z }

(Multiple Choice)
4.7/5
(35)

Let f(x,y)=1x2yf ( x , y ) = \frac { 1 } { x ^ { 2 } - y } .(a) Evaluate f(3,1)f ( 3 , - 1 ) .(b) Sketch the domain of ff .(c) What is the range of the function ff ?

(Essay)
4.7/5
(35)

If f(x,y)=62x2y2f ( x , y ) = 6 - 2 x ^ { 2 } - y ^ { 2 } , find fx(1,1)f _ { x } ( 1,1 ) and fy(1,1)f _ { y } ( 1,1 ) and interpret these numbers as slopes. Illustrate with sketches.

(Essay)
4.7/5
(38)

Use a linear approximation to estimate 2.92+4.12\sqrt { 2.9 ^ { 2 } + 4.1 ^ { 2 } } .

(Multiple Choice)
4.9/5
(24)

Find the directional derivative of the function f(x,y)=x2+y2f ( x , y ) = x ^ { 2 } + y ^ { 2 } at the point (1,2)( 1,2 ) in the direction θ=π2\theta = \frac { \pi } { 2 } .

(Multiple Choice)
4.9/5
(44)

Let x+y+zsin(xyz)=3x + y + z - \sin ( x y z ) = 3 . Use implicit differentiation to find δz/δy\delta z/\delta y when (x,y,z)=(1,0,2)( x , y , z ) = ( 1,0,2 ) .

(Multiple Choice)
4.8/5
(36)

In using Lagrange multipliers to minimize the function f(x,y)=x2+y2f ( x , y ) = x ^ { 2 } + y ^ { 2 } subject to the constraint that xy=2x y = 2 , what is the value of the multiplier λ\lambda ?

(Multiple Choice)
4.9/5
(32)

Find the greatest product three numbers can have if the sum of their squares must be 48.

(Short Answer)
4.8/5
(40)

Find the absolute maximum and minimum value of f(x,y)=2x+yf ( x , y ) = 2 x + y on the square region DD with vertices (0,0)( 0,0 ) , (0,2)( 0,2 ) , (1,2)( 1,2 ) , and (1,0)( 1,0 ) .

(Essay)
4.7/5
(42)

The graph of level curves of f(x,y)f ( x , y ) is given. Find a possible formula for f(x,y)f ( x , y ) and stretch the surface z=f(x,y)z = f ( x , y ) .  The graph of level curves of  f ( x , y )  is given. Find a possible formula for  f ( x , y )  and stretch the surface  z = f ( x , y )  .

(Essay)
4.9/5
(36)

Find three positive numbers xx , yy , and ZZ whose product is 343 and sum is minimum.

(Essay)
4.8/5
(33)
Showing 261 - 280 of 294
close modal

Filters

  • Essay(0)
  • Multiple Choice(0)
  • Short Answer(0)
  • True False(0)
  • Matching(0)