. as (x, y) (r, ), r - , - , ( 0).
, P (x, y) = 0 , (r1, ang1) (r2, ang2), , ( ) , :
r1 <= r
r2 <= r
ang1 <= theta
ang2 <= theta
r - , theta - , , .
(x, y) ( ) , wiki, .
, - , : http://mathforum.org/dr.math/faq/formulas/faq.polar.html
R = p sec(ang - omega)
p omega :
p = r1 * cos(ang1-omega) = r2*cos(ang2-omega)
cos(x-y) = cos(x)*cos(y) + sin(x)*sin(y),
[r1*cos(ang1) - r2*cos(ang2)] * cos(omega) = [r2*sin(ang2) - r1*sin(ang1)] * sin(omega)
, tan(omega) = sin(omega)/cos(omega) arctan ( tan), omega. , , p.
, - (R, ang) ,
R <= r
0 <= ang <= theta
min{ang1, ang2} <= ang <= max{ang1, ang2}
( r , theta - , ang1 - P1, ang2 - P2).
Rcos(ang-omega) = p
cos (ang-omega) , [min {ang1, ang2}, max {ang1, ang2}].
, .
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