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Mathematics
Mathematics
Problem
Expand and evaluate: a. a
∑
k
=
1
3
4
k
\sum_{k=1}^{3} 4k
∑
k
=
1
3
4
k
b. b
∑
k
=
1
6
(
k
+
1
)
\sum_{k=1}^{6} (k + 1)
∑
k
=
1
6
(
k
+
1
)
c. c
∑
k
=
1
4
(
3
k
−
5
)
\sum_{k=1}^{4} (3k - 5)
∑
k
=
1
4
(
3
k
−
5
)
d. d
∑
k
=
1
5
(
11
−
2
k
)
\sum_{k=1}^{5} (11 - 2k)
∑
k
=
1
5
(
11
−
2
k
)
e. e
∑
k
=
1
7
k
(
k
+
1
)
\sum_{k=1}^{7} k(k + 1)
∑
k
=
1
7
k
(
k
+
1
)
f. f
∑
k
=
1
5
10
×
2
k
−
1
\sum_{k=1}^{5} 10 \times 2^{k-1}
∑
k
=
1
5
10
×
2
k
−
1
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