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If x2+1/x2=38 x^2+1/x^2=38 findx1/xx-1/x

A10

B8

C6

D4

Answer:

C. 6

Read Explanation:

(x1/x)2=x2+21/x2(x-1/x)^2=x^2+2-1/x^2

(x1/x)2=x2+1/x22=382=36(x-1/x)^2=x^2+1/x^2-2=38-2=36

x1/x=36=6x-1/x=\sqrt{36}=6


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