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B e rü h r p u n k t d a r . R e c h n e ris c h g e h e n w ir g e n a u s o v o r. S o la n g e d e r B e rü h rp u n k t a b e r n o c h n ic h t
b e k a n n t is t, r e c h n e n w ir m it
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y f ( u ) ( x u ) f ( u )
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E in T a l in d e n B e rg e n w ird n a c h W e s te n v o n e in e r s te ile n F e ls w a n d , n a c h O ste n v o n e in e m
fla c h e n H ö h e n z u g b e g re n z t.
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a u fg e s te llt w e r d e n . A u c h h ie r w ird d e r Q u e rs c h n itt d e s G e lä n d e s d u rc h d a s S c h a u b ild d e r
F u n k tio n f b e s c h rie b e n .
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G e lä n d e q u e r sc h n itts e rre ic h e n k a n n .
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V ig a n e lla d e r e r ste O rt w e ltw e it, d e r s e it 2 0 0 6 im W in te r ü b e r g e s p ie g e lte s S o n n e n lic h t v e r fü g t.
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is t d ie B e d in g u n g d e r ta n g e n tia le n G re n z s itu a tio n . D ie M in d e sth ö h e w ird d u rc h d ie G re n z la g e d e r
T a n g e n te a n d e n B e r g rü c k e n b e s tim m t. D e r „ k u r v e n fe rn e “ P u n k t is t a ls o h ie r d e r T ie fp u n k t
T (0 |– 3 ,1 2 5 ), d a e r n ic h t d e n B e r ü h rp u n k t d a r ste llt.
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= ¢ × - +
N u n w ir d d e r k u r v e n fe rn e P u n k t T (0 |– 3 , 1 2 5 ) fü r x u n d y e in g e s e tz t:
3 ,1 2 5 f ( u ) ( 0 u ) f (u )
¢
- = × - +
A u flö s e n n a c h N u ll e rg ib t 0 f (u ) ( 0 u ) f ( u ) 3 ,1 2 5