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Given, x + 1/x = 5, then determine the value of x² + 1/x².

A25

B24

C26

D23

Answer:

D. 23

Read Explanation:

Given:

x+1x=5x + \frac{1}{x} = 5

Square both sides:

(x+1x)2=52\left(x + \frac{1}{x}\right)^2 = 5^2

x2+2+1x2=25x^2 + 2 + \frac{1}{x^2} = 25

Now subtract 2:

x2+1x2=252=23x^2 + \frac{1}{x^2} = 25 - 2 = 23

Final Answer:

23\boxed{23}


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