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Problems
Problem
Problem
If
x
x
x
satisfies
log
2
(
9
x
−
1
+
7
)
=
2
+
log
2
(
3
x
−
1
+
1
)
\log_2 (9^{x-1} + 7) = 2 + \log_2 (3^{x-1} + 1)
lo
g
2
(
9
x
−
1
+
7
)
=
2
+
lo
g
2
(
3
x
−
1
+
1
)
, then a.
x
∈
Q
x \in Q
x
∈
Q
b.
x
∈
N
x \in N
x
∈
N
c.
x
∈
{
x
∈
Q
:
x
<
0
}
x \in \{x \in Q : x < 0\}
x
∈
{
x
∈
Q
:
x
<
0
}
d.
x
∈
N
e
x \in N_e
x
∈
N
e
(set of even natural numbers)
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