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Mathematics
Problem
Find the value of
x
x
x
for which the infinite series
9
+
9
x
+
9
x
2
+
…
9+9x+9x^{2}+\dots
9
+
9
x
+
9
x
2
+
…
has sum
27
27
27
. a)
−
2
3
-\dfrac{2}{3}
−
3
2
b)
1
3
\dfrac{1}{3}
3
1
c)
2
3
\dfrac{2}{3}
3
2
d)
26
27
\dfrac{26}{27}
27
26
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