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National and Regional Contests
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MAA AMC
AMC 12/AHSME
1964 AMC 12/AHSME
4
4
Part of
1964 AMC 12/AHSME
Problems
(1)
Expression is equivalent to...
Source: 1964 AHSME Problem 4
9/12/2012
The expression
P
+
Q
P
−
Q
−
P
−
Q
P
+
Q
\frac{P+Q}{P-Q}-\frac{P-Q}{P+Q}
P
−
Q
P
+
Q
−
P
+
Q
P
−
Q
where
P
=
x
+
y
P=x+y
P
=
x
+
y
and
Q
=
x
−
y
Q=x-y
Q
=
x
−
y
, is equivalent to:
<
s
p
a
n
c
l
a
s
s
=
′
l
a
t
e
x
−
b
o
l
d
′
>
(
A
)
<
/
s
p
a
n
>
x
2
−
y
2
x
y
<
s
p
a
n
c
l
a
s
s
=
′
l
a
t
e
x
−
b
o
l
d
′
>
(
B
)
<
/
s
p
a
n
>
x
2
−
y
2
2
x
y
<
s
p
a
n
c
l
a
s
s
=
′
l
a
t
e
x
−
b
o
l
d
′
>
(
C
)
<
/
s
p
a
n
>
1
<
s
p
a
n
c
l
a
s
s
=
′
l
a
t
e
x
−
b
o
l
d
′
>
(
D
)
<
/
s
p
a
n
>
x
2
+
y
2
x
y
<
s
p
a
n
c
l
a
s
s
=
′
l
a
t
e
x
−
b
o
l
d
′
>
(
E
)
<
/
s
p
a
n
>
x
2
+
y
2
2
x
y
{ <span class='latex-bold'>(A)</span>\ \frac{x^2-y^2}{xy}\qquad<span class='latex-bold'>(B)</span>\ \frac{x^2-y^2}{2xy}\qquad<span class='latex-bold'>(C)</span>\ 1 \qquad<span class='latex-bold'>(D)</span>\ \frac{x^2+y^2}{xy} \qquad<span class='latex-bold'>(E)</span>\ \frac{x^2+y^2}{2xy} }
<
s
p
an
c
l
a
ss
=
′
l
a
t
e
x
−
b
o
l
d
′
>
(
A
)
<
/
s
p
an
>
x
y
x
2
−
y
2
<
s
p
an
c
l
a
ss
=
′
l
a
t
e
x
−
b
o
l
d
′
>
(
B
)
<
/
s
p
an
>
2
x
y
x
2
−
y
2
<
s
p
an
c
l
a
ss
=
′
l
a
t
e
x
−
b
o
l
d
′
>
(
C
)
<
/
s
p
an
>
1
<
s
p
an
c
l
a
ss
=
′
l
a
t
e
x
−
b
o
l
d
′
>
(
D
)
<
/
s
p
an
>
x
y
x
2
+
y
2
<
s
p
an
c
l
a
ss
=
′
l
a
t
e
x
−
b
o
l
d
′
>
(
E
)
<
/
s
p
an
>
2
x
y
x
2
+
y
2
AMC