Question

GO
TO
IT
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1,-1, 1,-1,1,-1, ..... upto 131 terms, then S 131 = ..........​

Answer 1

Answer:

Here, the 1st, 3rd, 5th,.... all odd terms are positive and 131th term is also odd, so it will be +1.

Answer 2

Answer:

Important formulas;(G.P)

Sn=n/2(a+l)

an=ar^(n-1)

Step-by-step explanation:

hope this helps you...