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Mathematics
Mathematics
Problem
1
+
2
⋅
2
+
3
⋅
2
2
+
4
⋅
2
3
+
⋯
+
100
⋅
2
99
1 + 2 \cdot 2 + 3 \cdot 2^2 + 4 \cdot 2^3 + \dots + 100 \cdot 2^{99}
1
+
2
⋅
2
+
3
⋅
2
2
+
4
⋅
2
3
+
⋯
+
100
⋅
2
99
equals (1)
99
⋅
2
100
99 \cdot 2^{100}
99
⋅
2
100
(2)
100
⋅
2
100
100 \cdot 2^{100}
100
⋅
2
100
(3)
1
+
99
⋅
2
100
1 + 99 \cdot 2^{100}
1
+
99
⋅
2
100
(4) none of these
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