How many values of n satisfy the following equation, where n is a non zero real number?
n + (1/n) = k
(1) k^2 = 4
(2) k = 2n
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Values of n
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Frankenstein
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Hi,
From(1) k^2=4 => k=-2 or +2
n+(1/n) = -2 or +2
n+1/n = -2 =>(n+1)^2/n = 0 => n = -1
n+1/n = 2 =>(n-1)^2/n = 0 => n = 1
So, n = -1 or +1
2 values of n satisfy
Sufficient
From(2) k=2 =>n+(1/n) = 2n =>n= 1/n
S0, n=-1 or +1
Sufficient
Hence answer D
Cheers!
From(1) k^2=4 => k=-2 or +2
n+(1/n) = -2 or +2
n+1/n = -2 =>(n+1)^2/n = 0 => n = -1
n+1/n = 2 =>(n-1)^2/n = 0 => n = 1
So, n = -1 or +1
2 values of n satisfy
Sufficient
From(2) k=2 =>n+(1/n) = 2n =>n= 1/n
S0, n=-1 or +1
Sufficient
Hence answer D
Cheers!
