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National High School Mathematics League
1983 National High School Mathematics League
2
Estimate
Estimate
Source: 1983 National High School Mathematics League, Exam One, Problem 2
February 21, 2020
Problem Statement
x
=
1
log
1
2
1
3
+
1
log
1
5
1
3
x=\frac{1}{\log_{\frac{1}{2}} \frac{1}{3}}+\frac{1}{\log_{\frac{1}{5}} \frac{1}{3}}
x
=
l
o
g
2
1
3
1
1
+
l
o
g
5
1
3
1
1
, then
(A)
x
∈
(
−
2
,
−
1
)
(B)
x
∈
(
1
,
2
)
(C)
x
∈
(
−
3
,
−
2
)
(D)
x
∈
(
2
,
3
)
\text{(A)}x\in(-2,-1)\qquad\text{(B)}x\in(1,2)\qquad\text{(C)}x\in(-3,-2)\qquad\text{(D)}x\in(2,3)
(A)
x
∈
(
−
2
,
−
1
)
(B)
x
∈
(
1
,
2
)
(C)
x
∈
(
−
3
,
−
2
)
(D)
x
∈
(
2
,
3
)
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