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if n is a positive odd integer
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16 Nov 2019, 02:24
16 Nov 2019, 02:24
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Question Stats:
68% (01:01) correct
31% (01:14) wrong based on 54 sessions
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If n is a positive odd integer and \(k=n^3+2n\), what is the value of \((-1)^k - (-1)^{k+1}\) ?
A. -2
B. -1
C. 0
D. 1
E. 2
A. -2
B. -1
C. 0
D. 1
E. 2
Re: if n is a positive odd integer
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18 Nov 2019, 22:34
18 Nov 2019, 22:34
3
Carcass wrote:
If n is a positive odd integer and \(k=n^3+2n\), what is the value of \((-1)^k - (-1)^{k+1}\) ?
A. -2
B. -1
C. 0
D. 1
E. 2
A. -2
B. -1
C. 0
D. 1
E. 2
We are given that n is a positive odd integer.
now (odd)^odd = odd and even(odd) = even
so k = odd + even = odd.
k + 1 = odd + odd = even
now (-1)^odd = -1 and (-1)^even = 1
\((-1)^k - (-1)^{k+1}\) = -1 -1 = -2
OA - A
Re: if n is a positive odd integer
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06 Jan 2022, 09:37
06 Jan 2022, 09:37
Expert Reply
