223 Textbook Errors

Please email me any corrections to the textbook - typos, grammar, or mathematical errors.  I will give credit for the first one I receive and post them here.

Discovered by students thus far this semester:

In "Active Calculus: - Multi variable:  our goals",  in the last bullet  it says " To strengthen students’ written and oral communicating skills by having them write about and explain aloud the key ideas of multivariable calculus" and it should say "communication" instead of "communicating".

in the first paragraph of chapter 9.1 after the motivating questions. Discuss is spelled "dicusss".

the first paragraph of section 9.2, the word variables is spelled 'veriables'.

in the first paragraph of 9.2. Calculate is spelled “calculuate.”

Section 9.6, the last activity, says "How do your responses change to all three of the preceding question if-" but "question" should be plural.

On page 140, it reads: "It would take us too far afield to provide a rigorous dicussion of differentiability of functions of more than one
variable (see Exercise 10.4.15) for a little more detail), so..." but that first closing parenthesis shouldn't be there.

Activity a. on page 178 misspells "maximum" as "maximimum".  Also on page 180, there's a space in the middle of "points" so it says
"these critical point s and at the endpoints...".  Page 182: "To find the hottest and coldest point on the boundary," "points" needs to be plural for logical reasons (one point can't be both the hottest and the coldest), and it's already plural everywhere else in the section.  Page 183: "Find the absolute maximum and absolute minimum value of f on R." "values" needs to be plural for logical reason. 

Page 187, exercise 19, the order of the quotes is wrong: “‘The Only Critical Point in Town” Test’ should be either single-double-double-single, or double-single-single-double.

On page 280, the description following Definition 12.2 should say "...C is a piecewise smooth curve traced out from..." Right now, it reads "...C is a piecewise smooth curved traced out from..."

In section 12.4, page 294, last paragraph it says "pair of paths from oine point to the other" it should say "one".

Section 12.4 on page 300 in the summary. The second bullet point says, "and only if the ciruclation around." It is supposed to be circulation.

In section 12.4 Activities 12.10 and 12.11 are duplicates. 



These are those from last time.  You might check to see if they have been fixed yet. 

in section 9.1 on page 6 immediately after activity 9.3 there is an error in the textbook.   the textbook says "The xy-plane satisfies z = 0, the xz-plane satisfies y = 0, and the yz-plane satisfies z = 0" but it should say "The xy-plane satisfies z = 0, the xz-plane satisfies y = 0, and the yz-plane satisfies [x] = 0"

on page 55 section 9.5 down at the bottom of the page, "That is, we may write the equation of a plane as ax + by + cz = d where where d = n · hx0, y0, z0i." They say where twice in a row.

On page 70, section 9.7 at the very top, they describe the product rule for scalar functions as (d/dx)[f(x)*g(x)]=f(x)*g'(x)+g'(x)*f'(x) which is incorrect because as you know, the song is wrong. It should write (d/dx)[f(x)*g(x)]=f(x)*g'(x)+f'(x)*g(x).

On page 160 in section 10.7, the fourth bullet of definition 10.5 defines an absolute minimum point then claims "the value of f at an absolute minimum point is the maximum value of f." This is false because the value of f at an absolute minimum point is the minimum value of f, while the maximum value of f is the value of f at an absolute maximum point.

on page 163, and it is right at the top of the page and it says, "...whether a critical point is a local maximum, local maximum, or neither." the correction is "...whether a critical point is a local maximum, local minimum, or neither."

In section 10.7 on page 172, part (d) of question #6 reads "Find the maximum value of V on the boundary of the region R, and the determine the dimensions of a bag with maximum volume on the entire region R."  So "and the determine the dimensions" should read "and then determine the dimensions" replacing the first "the" with "then".

On page 246, The second second of the Introduction paragraph reads " In a similar way, there there turn out to be two additional natural coordinate systems"  They wrote the word "there" twice.

In section 12.2, page 278, in the introduction, it says "However, things more complicated when an object’s movement is not in a straight line..." I believe it should say "However, things are more complicated..."

In the summary of 12.2 on page 284 "A line integral measures of a vector field along an oriented curve measures the extent to which the vector field points in a direction consistent with the orientation of the curve." has many extra words and would better be "A line integral measures the extent to which the vector field points in a direction consistent with the orientation of the curve."