On Algebra Education in Russian Schools
175
These two groups of textbooks, in our view, reflect a fundamental
difference between two conceptions of basic and advanced courses in
mathematics.
4.2.2
The study of algebraic expressions in grades 10–11
The content of the material pertaining to the study of algebraic
expressions in high school, like the other sections of the course in
mathematics, is prescribed by the Standard. It should be noted that
certain topics are listed in the Standard in italics; these topics must be
included in the curriculum but are not part of the final attestation.
Also, the Standard does not require that the high school curriculum
include a section specifically devoted to numbers. Issues connected
with expanding the concept of number thus belong to the algebraic
part of the curriculum.
As can be seen from the passages from the Standard cited above,
the content that pertains to the study of algebraic expressions differs
substantially in the basic and advanced courses. Their common part is
connected with the study of roots of degree n, powers with rational
exponents, and the logarithm of a number. In these sections, students
receive virtually the same set of theoretical facts, so the main difference
is in the depth of their assimilation of this material.
As an illustration of this difference, consider how the students learn
the topic “Roots of the nth degree and their properties.”
In the textbook by Kolmogorov et al. (2007), the emphasis is
on learning definitions and algorithms. Thus, in studying this topic,
students must assimilate certain techniques for transforming algebraic
expressions. At the mandatory level, they must learn how to solve the
following types of problems:
• Move a factor outside the radical sign (a > 0, b > 0):
(a)
6
√
64a
8
b
11
;
(b)
5
√
−128a
7
.
• Move a factor inside the radical sign (a > 0, b > 0):
(a)
−b
4
√
3
; (b) ab
8
5b
3
a
7
. (Kolmogorov et al., 2007, p. 205)
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Russian Mathematics Education: Programs and Practices
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176
Russian Mathematics Education: Programs and Practices
A somewhat higher level is illustrated by the following problem:
• Put the following expression in the form of a fraction whose
denominator does not contain a radical: (a)
1
3
√
2
−
3
√
3
; (b)
2
a−
3
√
b
.
(Kolmogorov et al., 2007, p. 206)
The corresponding technique, as we will see below, is used in solving
irrational equations.
In the advanced textbooks of Dorofeev, Kuznetsova, and Sedova
deliberately learning to carry out elementary algorithms is not an end
in itself. Transformations involving radicals as a rule play a secondary
role and have the character of technical work, which must be carried
out in the process of solving more substantive problems.
For comparison, consider several problems on the topic examined
above from the problem book of Dorofeev, Sedova, and Troitskaya
(2010). Of course, as in Kolmogorov et al.’s (2007) textbook, this
problem book includes problems that involve elementary simplifica-
tions of expressions with radicals. But this problem book also examines
the opposite problem: under what conditions (constraints on variables)
is an already-transformed expression equal to the one given? (Dorofeev,
Sedova, and Troitskaya, 2010, p. 16).
For what x and y is the expression (y − 5)
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