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Putnam
Putnam 1939
B1
Putnam 1939 B1
Putnam 1939 B1
Source:
August 20, 2021
Putnam
Problem Statement
The points
P
(
a
,
b
)
P(a,b)
P
(
a
,
b
)
and
Q
(
0
,
c
)
Q(0,c)
Q
(
0
,
c
)
are on the curve
y
c
=
cosh
(
x
c
)
.
\dfrac{y}{c} = \cosh{(\dfrac{x}{c})}.
c
y
=
cosh
(
c
x
)
.
The line through
Q
Q
Q
parallel to the normal at
P
P
P
cuts the
x
−
x-
x
−
axis at
R
.
R.
R
.
Prove that
Q
R
=
b
.
QR = b.
QR
=
b
.
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