Начертательная геометрия
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#$ ! $ T(ABCD) II W ( .4.11)
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= . 4.13 |
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= . 4.15 |
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4.4. ( % %% # "&+"& % |
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+ , ' -) . % - ) bk y, ) z ( . 4.19).
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7 ( , ' -" " ( . 4.20). <+ " - " " " D D . B " " , -+ " ( .
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4.5. = %: " #" "/ % # *:"0 % # "&+"& %
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@ . 4.24 ' " P ( CDE) ) -D' AB, D' K. : k a b . C "K P D ( , 1 2).) D D, " D. $ KAB 1-2, K -AB P , , .
= . 4.23 |
= . 4.24 |
( , ' D', "-' 3, D &,D Q ( MN) ( . 4.25 4.26).
$ D D' .
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1.D AB " D P ( + D' D);
2.D MN Q ( CDE) " P;
3.$ AB MN P, - D ( K), -AB D Q.
4.# D D AB Q.
= . 4.25 |
= . 4.26 |
C AB -' D' ( D' ).
$, M L ' D' AB CD: M CD, L AB. * ) m l D . "-" V ,L ( l) M ( m),M ) D ., AB K - " CDE ) .K D AB " CDE N, -k n .
@ " AB -1 2 (1 DE, 2 AB), ' ' D' AB DE. ) ,H, 1,
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D + 2. @ " 1 -2. ( AB " 'DEK ( k2).
4.6. = %: " #" "/ % # "&+"& 0
# ' ". , ", .D ' .
+ , D' -D- ' " .
@ , D ( . 4.27) -, D ( ABC). - , D , ' , " .
= . 4.27 |
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/ D , , . 4.28, D " -D' , -,( " ), . : - .
= . 4.28
( -D' ,. @ . 4.29 -) -D' , - , . 4.30 " -D' (- " ABC) c D ' " ( " DEF).
@ ) ( . 4.29) -Pv DE DF " DEF ) -n m . "-M N .
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= . 4.29 |
= . 4.30 |
# ' D D' . " D (- ) "( . 4.31). -' D . D ' D ,' D ' " - .
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@ . 4.32 " - . = + D' . -" ) -D'P AC Q BC - " ABC. P " DEF 1- 2. " 1-2 ac "-D D M(m) . Q -" DEF 3-4. "3-4 bc " D D N(n) . : ( , , -, , .
M " -' D D' .