1. page 12 problem 33: replace "100" by "99"
2. page 126 line 3: replace "f(U)\subset V" by "f(U)\backslash\{x_0\})\subset
V"
3. Page 303 line 15: replace the display by
1\leq c_0\leq b_1< c_1< b_2< \cdots < b_i
4. Page 303 line 17: replace "E\subset A" by "E=A\cap (\{1,2,\ldots, n\}\backslash
\{c_0,b_1,c_1,b_2,\ldots, b_m,c_m\})"
5. Page 405 line 9 from the bottom: repalce "\mbox{Re}(-a_2z^{-2}-\cdots -a_nz^{-n})" by
"\mbox{Re}(-a_{n-2}z^{-2}-\cdots -a_0z^{-n})"
6. Page 406 line 8 from the bottom: add
"\leq 9(|z|^{-2}+|z|^{-3}+\cdots +|z|^{-n})"
at the begining of the line in the second line of the display.
7. Page 263 line 5: replace "4^1+1^2" by "4^1+1^2+1"
(add a 1)
8. Page 324 line 21: replace "S_n" by "S_9"
9. page 294 problem 856: replace the second occurence of the word "edges" by
"vertices"
10. page 292 first line: after "complete graph" add " with $R(p,q)$ vertices"
11. page 515 line 15: insert "Mathematical" between "Romanian" and "Olympiad"
12. page 68 line 5 from the bottom: replace "positive" by "nonnegative"
13. page 79 line 4 from the bottom: delete the comma between "mechanics" and
"observable"
14. page 296 line 4 from the bottom: insert "of" between "and" and "the
position"
15. page 312 line 10: delete the word "combinatorial"
16. page 132 line 15: - delete the bar over z in $\psi(z)=f(z)-f(-\bar{z})$
- on next line, delete the entire content of the paranthesis; the phrase
should end with the word "continuous"
- on next line delete the bar over z_0
- in the display, delete the two bars over z_0
To conclude, in the entire paragraph there should be no bars.
17. page 148 lines 8 and 6 from the bottom: to be very rigorous, the argument
of the natural logarithm in the two displays should be taken in absolute
value. So we should have "\ln |\sin x+\cos x|" instead of
"\ln (\sin x+\cos x)", three times.
18. page 103 line 9: the two exponents in the general term formula should both
be $n$, not $m$.
19. Replace the first example from section 2.2.3. page 52 with
the following:
\bes
20. Page 718 line 1: 7^z should be 7^zx
21. On the back cover there is a repeated "to" on the last line.
22. Page 7 line 1: add "a" before $1\times 1$.
23. Page 93 line 21: in the statement of problem 286 it would look much better
if instead of "$(\sin n)_n$" there was "$(\sin n)_{n\geq 1}$"
24. Page 183 last line: replace {\bf i} {\bf j} {\bf k} by \vec{i} \vec{j}
\vec{k}
25. Page 102 line 9: replace "$\lambda _{1,2}=\frac{1\pm \sqrt{5}}{2}$" by
"$\lambda _1=\frac{1-\sqrt{5}}{2}$ and $\lambda_2=\frac{1+\sqrt{5}}{2}$"
26. Page 206 line 11: "Let $ABC$ be a convex quadrilateral" should be "Let
$ABCD$ be a convex quadrilateral"
27. Page 254 line 15: put ( ) around f(2n+1) and f(2n) so that they look like
(f(2n+1))^2-(f(2n))^2
28. Page 585 line 11: insert "not" between "is" and "identically"
29. Page 684 line 13: "\lfloor x_1+\frac{1}{2}\rfloor" should read "\lfloor nx_1+\frac{1}{2}\rfloor"
an n is missing
30. Page 185 line 4 from the bottom: the third term in the equation should be
"\frac{(x+f(0))^2-(x-y)^2-(f(0))^2+y^2}{2x}"
31. Page 112 line 4 from the bottom: replace "\frac{1}{2}(x+1)" and "2(x+1)" by "\frac{1}{2}(x+2)"
and "2(x+2)"
32. Page 112 line 2 from the bottom : replace "x\cdot \frac{x+1}{2}" by "x\cdot \frac{x+2}{2}"
and "2x(x+1)" by "2x(x+2)"
33. Page 331 line 7: Delete the sentence that starts with "We assume in" and
ends with "problem."
34. Page 610 line 4 from the bottom: the vertical bars around the cross product of OM and OP should
be doubled, therefore they should be \| and \|
35. Page 610 line 1 from the bottom: in the bracket, the \times between AE and
AC should be +
36. Page 199 delete lines 13 and 14, namely delete the sentence that starts
with "An alternative approach..."
37. Page 730 line 4 from the bottom: delete the comma between $r-1$ and
transpositions.
38. Page 547 line 4 from the bottom: it should be $f'(x)\geq f'(1)$
39. Page 159 line 13: replace $f'(0)>0$ by $f'(1)>0$.
40. The solution to problem 818 at page 279 is wrong and cannot be fixed.
Here is a possible replacement:
Solution (to be replaced at page 722, line 4):
41. Page 304 problem 882: in the first sum, the summation
should be from "i=0" instead of "j=0"
42. Page 761 line 12: $\{0,1\}^n$ should be $\{0,1\}^{p+q+1}$.
43. Page 760 line 9: the expression in the display should be
$\sum_{k=0}^m{m\choose k}{{n+k}\choose m}$. The expression written
there has nothing to do with the problem.
44. Page 30 line 13: in the display there should be $(n-1)^2$
instead of $(n^2-1)^2$.
45. Page 41: problem 122 is silly, it should be ignored.
46. Page 268 line 2 from the bottom: the $a_n$ in $x\equiv a_n$
should be $a_k$.
47. Page 269 line 8: Warsawa should read Warszawa.
48. Page 711 line 7 from the bottom: Warsawa should read Warszawa.
49. Page 132 in the solution to the example, all the bars over z and z_0
should be ignored (there are 5 of them). As such, "$-z$ is diametrically
opposite to $z$".
50. Page 480 the third display: the "+4" in the denominator should
be a "+2".
51. Page 255 line 12: the union of sets should be intersection of sets
(because of de Morgan's law).
52. Page 373 line 9 from the bottom: In the display, there is an
extra bracket in the term |\epsilon(z-\epsilon)|; delete it.
53. Page 330 line 2: replace "x_j>0, x_{j+1}<0", and "x_j+x_{j+1}" by
"x_j>0, x_{j+1}\leq 0". The original condition is too strong (e.g 2,3,-4) and
not needed.
54. Page 324 lines 3, 5, 6: replace "16" by "15".
55. page 323 line 4 from the bottom: while the solution is not incorrect
as is, the number 29 can be replaced by 27 in the argument, namely
21 plus the 6 numbers that can have repeated prime factors.
56. page 84 line 2 from the bottom: replace $n$-dimensional
sphere by $n-1$-dimensional sphere.
57. page 86 line 18: replace $K_0$ by $K_1$.
58. page 86 line 19: replace $K$ by $K_1$.
59. page 424 line 12: in the last sum there should be a cosine
before $k(m+j)\alpha$.
60. page 555: The solution to problem 497 is wrong. I think
the following fix works. Replace replace everything starting
with the second line at the bottom of page 555 to the second equation
on top of page 556 by
61. page 239 line 12: in the expression on the left-hand side, the denominator
of the first factor in the second term should be 2z not 2x.
62. page 351 line 2: "9/2" should read "13/2".
63. On the front cover of the book, on the last line of the design
there is a parenthesis missing in "(x,y)"
64. page 41 line 7: the "2" in the parenthesis should be a "w"
65. page 100, in the determinant at the bottom of the page, on
the first row of the determinant there is a "-" missing in front
of "a_{k-1}"
66. This is not a typo, just a remark. The answer to problem 298 could
also be written as "a_k = \lfloor{\frac{k}{2}}\rfloor^2 + \lceil{\frac{k}{2}}\rceil^2"
67. page 50, line 8 from the bottom: "m^3-3m^3+27m-20" should read
"m^3-9m^2+27m-20"
68. page 53. lines 13, 14, 16: in all the summations, the "k" should be "n"
69. page 115, in the statement to problem 341, the condition should
be "p\neq -1"
70. Another way to write the answer to problem 298 is
"x_n = \lfloor{\frac{n}{2}}\rfloor^2 + \lceil{\frac{n}{2}}\rceil^2"
71. page 464 line 8 from the bottom, "u^n and \bar{u}^n" should read
"u and \bar{u}"
72. page 464 line 4 from the bottom, S_2 should be "S_2=1-a"
\begin{example}
Find all cubic polynomials $P(x)$ with the property
that $P(x)$ is a multiple of $P''(x)$.
\end{example}
Set $P(x)=Q(x)P''(x)$, with $Q(x)$ a quadratic polynomial.
Differentiation twice this relation we obtain
\begin{eqnarray*}
P''(x)=Q''(x)P''(x)+Q'(x)P'''(x).
\end{eqnarray*}
Hence $P''(x)(1-Q''(x))=Q'(x)P'''(x)$. We deduce that
$P'(x)$ is a constant multiple of $Q'(x)$. Incorporating the
constant into $Q(x)$, we see that $P(x)=Q(x)Q'(x)$ for
some quadratic polynomial $Q(x)$. It is not hard
to check that each polynomial of this form has the
desired property.
\ens
Find all positive integers $x,y$ such that $15^x-6^y=9$.
Clearly $x=y=1$ is a solution, while $y=2$ does not yield a solution. If $y>2$, then reducing
modulo $4$ we obtain that $x$ is even, $x=2n$. The equation can be rewritten as
$15^{2n}-9=6^y$ or
\begin{eqnarray*}
9(5^n\cdot 3^{n-1}+1)(5^n\cdot 3^{n-1}-1)=2^y\cdot 3^y.
\end{eqnarray*}
Because $y>2$, the left-hand side should have an additional factor of $3$. This can
only happen when $n=1$, so the only other solution to the given Diophantine equation
is $x=2,y=3$.
" Similarly
\begin{eqnarray*}
(-1)^m\int_0^\pi f^{(2m)}(x)(n\sin x+sin nx)dx =(na_1-n^{2m}a_n)\frac{\pi}{2}\geq 0.
\end{eqnarray*}"