In contrast to virtually all other textbooks, the textbook of M. I.
attention to physical and technological applications of mathematics.
and proofs...play the role of instructions and descriptions” (p. 3).
person” (p. 4).
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Russian Mathematics Education: Programs and Practices
concept of the limit). Then the derivative is introduced, following
Leibniz, as the slope of a tangent; from these two examples, a new
operation is derived — differentiation — and the ordinary definition
of the derivative is given.
In investigating a function, the criteria for monotonicity and for the
presence of extrema are presented using a mechanical interpretation
of the derivative as velocity. In contrast to most other textbooks,
considerable attention is devoted here to the concept of the differential
as the principal part of the change of a function. Numerous physical
applications are examined in accordance with the same schema: if
the differential of one physical magnitude — such as, work — is
proportional to the differential of another physical magnitude — such
as displacement, dA = F(x)dx — then force equals the derivative
of work with respect to displacement, F(x) =
dA
dx
. The concluding
conversation introduces the concept of linearization: a small change in
one magnitude brings about a proportional change in another.
Trigonometric functions are introduced in connection with the
description of periodic processes; in particular, the author examines
uniform motion along a circle. Formulas for the derivatives of the
sine and cosine are derived using the coordinates of the vector of
the instantaneous velocity, which is perpendicular to the radius vector
of a point on the circle. Using these formulas, the author finds
approximate formulas for computing sines and cosines for small x:
sin x ≈ x, cos x ≈ 1 −
x
2
2
.
The integral is defined as the area of a curvilinear trapezoid, after
which the Newton–Leibniz formula related to its connection with
antiderivatives is proven. It is then stated that the integral can be defined
in four ways: as the area under the curve of a function, as the limit
of sums, as the change in the antiderivative, and as a function of an
interval.
In this way, Bashmakov’s textbook introduces the material “on a
physical level of rigor,” maintaining this level throughout the text.
In spirit, this textbook is closer to the calculus of Newton and
Leibniz than the calculus of Cauchy and Weierstrass. At the same
time, both the conceptual aspects and the techniques are laid out
clearly and comprehensively. The language of the textbook is free and
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Elements of Analysis in Russian Schools
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not “scientific-sounding” (for example, the chapter “Equations and
Inequalities” bears an epigraph from George Orwell: “All animals are
equal, but some animals are more equal than others”). In order for
students to understand this textbook, however, it is desirable that they
should have a decent knowledge of physics, which is not always the case.
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