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Visual didactic materials
The series «The first quarter
of the trigonometrical circumference»
of the collection «The trigonometrical circumference» These films can be reproduced on any computer having WINDOWS version 95 (and higher versions) without an additional installation of special programmes as they are made in EXE format. The principle of operation: the changing of frames is executed by pushing of a printed(graphical) button. Movement is is possible both “forward” and “backward”. Slidefilms are meant for group study and can be used by a teacher at school lessons spontaneity.The principle of operation the film offering by us gives an opportunity to stop at the frames demanding special attention. 
Brief contents of the series  
¹1. The remarkable angles of the first quarter of the trigonometrical circumference  

The film shows how to construct remarkable angles
rather exactly without a protractoron by means of a pen and a pair of compasses on plotted paper .
It’s useful to pay attention of students to comfortable for calculations and corresponding constructions
significances of the remarkable angles, for which angles of 0, 30, 45, 60 and 90 degrees of the first
quarter of the trigonometrical circumference are taken.  
¹2. The remarkable radicals on the radiuses of the first quarter of the trigonometrical circumferenñe  

The film shows how to mark some special numbers which are called the remarkable radicals
on the radiuses of the trigonometricalcircumferenñe there rather precise on plotted paper.
It’s useful to pay attention of students to
comfortable for calculations and corresponding constructions
significances of the remarkable radicals, which are the coordinates of the points forming on the first
quarter of the trigonometrical circumference.  
¹3. The remarkable sines and cosines of the angles of the first quarter of the trigonometrical circumference  
The film shows how to determine the significances of sines and cosines of the remarkable angles on the base of already learnt ways
The connection of the remarkable angles of the first quarter of the trigonometrical circumference
and corresponding remarkable sines and cosines as which sines and cosines of the remarkable angles are implied
should be paid attention of students to. 

¹4. The radian measure of the remarkable angles of the first quarter of the trigonometrical circumference  

The film shows how to mark sines and cosines of the remarkable angles of the first quarter of the trigonometrical
circumference expressed in radians on the line of sines and cosines. Besides,the comparison of equal significances of remarkable sines and cosines
for different angles takes place.
The way the radian and the degree measures of the remarkable angles are connected should be paid attention to.


¹5. The remarkable radians and numbers of the first quarter of the trigonometrical circumference  

The film shows how to determine rather exactly the position of the remarkable radians and radicals on the axis of special trigonometrical system of coordinates hith help of of the models of the first quarter of the trigonometrical circumferenñe there on plotted paper.  
¹6. The graph of sine in the interval from 0 to Ï/2 on the plotted paper  

The film shows how to construct the graph of sines and cosines in the interval from 0 to Ï/2
with help of the remarkable points of the first quarter of the trigonometrical circumferenñe on plotted paper.
The students are supposed to be given the basic ideas of
construction of the graph of sines in the trigonometrical coordinate system, which is determined as a curve passing through
the remarkable points of the sine.  
¹7. The graph of cosine in the interval from 0 to Ï/2 on the plotted paper  

The film shows that construction of the remarkable cosines on plotted paper
also takes place on the axis of significance of the trigonometrical function.The remarkable radians are also laid
of the first quarter of the trigonometrical circumferenñe on the axis of its argument.
The students are supposed to be given
the basic ideas of peculiarities of construction of the graph of cosines in the trigonometrical system of coordinates,
which is also determined as a curve passing through
its remarkable points .


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