The mean of x and 1/x is N. Then the mean x2 and 1/x2 is(1) N2(2) N

1.	The mean of x and 1/x is N. Then the mean x2 and 1/x2 is(1) N2(2) N2 - 2(3) 2N2 -1(4) 4N2 -2
Answer» (3) 2N² -1 x + \(\frac{1}{x}\) = 2N x²+ \(\frac{1}{x^2}\) + 2 = 4N² x²+ \(\frac{1}{x^2}\) = 4N²- 2 ∴ mean of x²and \(\frac{1}{x^2}\) = \(\frac{1}{2}\) (4N²- 2) = 2N²- 1

The mean of x and 1/x is N. Then the mean x2 and 1/x2 is(1) N2(2) N2 - 2(3) 2N2 -1(4) 4N2 -2

Answer»

(3) 2N² -1

x + \(\frac{1}{x}\) = 2N

x²+ \(\frac{1}{x^2}\) + 2 = 4N²

x²+ \(\frac{1}{x^2}\) = 4N²- 2

∴ mean of x²and \(\frac{1}{x^2}\) = \(\frac{1}{2}\) (4N²- 2)

= 2N²- 1

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The mean of x and 1/x is N. Then the mean x2 and 1/x2 is(1) N2(2) N2 - 2(3) 2N2 -1(4) 4N2 -2

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