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Mathematics
Mathematics
Problem
Find the sum
3
+
6
+
12
+
24
+
48
3 + 6 + 12 + 24 + 48
3
+
6
+
12
+
24
+
48
: a. by direct addition b. using
S
n
=
u
1
(
r
n
−
1
)
r
−
1
S_n = \frac{u_1(r^n - 1)}{r - 1}
S
n
=
r
−
1
u
1
(
r
n
−
1
)
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