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tanyajoseph
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looks like the following values would fit the sequence... going upto a ( 8 )tanyajoseph wrote:Can someone kindly explain this?
a(0) = 0
a(1) = 1
a(2) = -1
a(3) = 3
a(4) = -3
a(5) = 5
a(6) = -5
a(7) = 7
a ( 8 ) = -7
Statement (1): If n is odd, terms upto n-1 (n-1 is even) would cancel each other out and the sum would be positive
Statement (1) is sufficient
Statement (2): For a(n) to be positive, n has to be odd. The previous argument then applies. Sufficient.
Answer [D], each alone.
