' The London School of Economics and Political Science
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Department of Economics
SG/JM 28th June, 1976.
Professor Steindl,
A-llo3,
"ien Postfach 91,
AUSTRIA.
Dear Professor Steindl,
My reaction to your letter of 13th June was, it appears,too quick and
ill-founded. Over the weekend I was trying to reproduce my original discussion
of the equation:
I
(1) +
where a, b and h are all non-negative, and a < 1. Unfortunately, I could
not find my notes with the discussion (of ten years ago!), so that I have had
to do it again. However, the results are different than I thought they were.
Let 1^ = E e^. On substituting to (1) we have
= a + b |jL-e^J
a + i a)
(2) e
Let X = a + i a). Since e
(3)
a
= e (cos a) + i sin a)) , we have
a , . , -ha ,
e cos a) = a + b- be cos h a)
t a\ a , -ha
(4) e sin a) = b e
a i + h
From Eq.4 e = (b sin h w/sin ai) S n (w) . Svibstituting into (3) gives
—h
(5) <f> (to) = n (u) cos a) + b n (w) cos h ai = a + b
Continued..
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