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1949-56 Chisinau City MO
36
Chisinau MO p36 1949-56 VIII-IX sum 1+ 2q + 3q^2 +...+nq^{n-1}
Chisinau MO p36 1949-56 VIII-IX sum 1+ 2q + 3q^2 +...+nq^{n-1}
Source:
March 15, 2021
algebra
Sum
Problem Statement
Calculate the sum:
1
+
2
q
+
3
q
2
+
.
.
.
+
n
q
n
ā
1
1+ 2q + 3q^2 +...+nq^{n-1}
1
+
2
q
+
3
q
2
+
...
+
n
q
n
ā
1
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