, , . , , , z ; ( z), . (. 6, ). ab, , , = b - - . ( b) , , ab .
P , , , . . Px. - , ; , P1x P2x.
. 6, , Px = ab, ab = AC, a ∆ , AC = Pcosa. ,
Px = Pcosα,
. . .
. , (. 6, ) α, π/2< α <π. ,
P1x = P1 cosα = P1 cos(π - β) = - P1 cos β.
, P1x , 1 b1 . α = 0 (. 6, ), . . , cos 0 =1 P2x = P2cos 0 = P2, α = π, . . , , cos π = - 1 P3x = P3 cos π = P3; α = π / 2, . . , cos (π / 2) = 0 P4x = = P4cos(π /2) = 0.
. 6. .
, , , . .
, (. 7)
α x = (, x) α = (, ),
Pkx = Pkcs α Pk = Pkcos αy; αy= (90˚- α x), Pk=Pksin α x.
( ).
, Pkx Pky , ∆ (. 7) , Pk = .
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. , ABCDE, = (. 8). , .
:
P1x = 1b1, P2x = b1cl, P3x = c1d1 P4x = d1e1.
:
P1y = a2b2, P2y = b2c2, P3y = c2d2 P4y = d2e2.
. 8 , , ( ) ( ), .
, , :
.8 ,
= 11 = a1b1 + b1cl + cl dl d1e1; = 22 = a2b2 + b2c2 - c2 d2 d2e2.
, , =0. , , ..
= = 0;
= = 0.
, , .
. 7.
. . 8.
.
.
, . . , , .
, (. 9), ( ).
, , , . , , , .
. .
, , , , . . (.10).
, (), . , . (, ). , , , .
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, , - , (. . 9 10), .
.10. .
. 9. .
P h (. . 9) , . P h, .
. M, . .
M= P h.
, , , . , . 11, (, ) M1= P1 h1, . 11, (, ) M2= - P2 h2. () , . (.).
. 11. .