let f, g be Function of (Topen_unit_circle c[10] ),(R^1 | (R^1 ].0 ,1.[)); ( ( for p being Point of (Topen_unit_circle c[10] ) ex x, y being real number st
( p = |[x,y]| & ( y >= 0 implies f . p = (arccos x) / (2 * PI ) ) & ( y <= 0 implies f . p = 1 - ((arccos x) / (2 * PI )) ) ) ) & ( for p being Point of (Topen_unit_circle c[10] ) ex x, y being real number st
( p = |[x,y]| & ( y >= 0 implies g . p = (arccos x) / (2 * PI ) ) & ( y <= 0 implies g . p = 1 - ((arccos x) / (2 * PI )) ) ) ) implies f = g )
assume that
A26:
for p being Point of (Topen_unit_circle c[10] ) ex x, y being real number st
( p = |[x,y]| & ( y >= 0 implies f . p = (arccos x) / (2 * PI ) ) & ( y <= 0 implies f . p = 1 - ((arccos x) / (2 * PI )) ) )
and
A27:
for p being Point of (Topen_unit_circle c[10] ) ex x, y being real number st
( p = |[x,y]| & ( y >= 0 implies g . p = (arccos x) / (2 * PI ) ) & ( y <= 0 implies g . p = 1 - ((arccos x) / (2 * PI )) ) )
; f = g
hence
f = g
by FUNCT_2:113; verum