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If (x - (1)/(x)) = 5 then (x^(2) + (1)/(...

If `(x - (1)/(x)) = 5` then `(x^(2) + (1)/(x^(2)))` = ?

A

25

B

27

C

23

D

`25 (1)/(25)`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equation \( x - \frac{1}{x} = 5 \) and find \( x^2 + \frac{1}{x^2} \), we can follow these steps: ### Step 1: Square both sides of the equation Starting with the given equation: \[ x - \frac{1}{x} = 5 \] We square both sides: \[ \left(x - \frac{1}{x}\right)^2 = 5^2 \] This simplifies to: \[ x^2 - 2 \cdot x \cdot \frac{1}{x} + \left(\frac{1}{x}\right)^2 = 25 \] ### Step 2: Simplify the left side The middle term simplifies as follows: \[ -2 \cdot x \cdot \frac{1}{x} = -2 \] So we can rewrite the equation as: \[ x^2 - 2 + \frac{1}{x^2} = 25 \] ### Step 3: Rearrange the equation Now, we can rearrange the equation to isolate \( x^2 + \frac{1}{x^2} \): \[ x^2 + \frac{1}{x^2} = 25 + 2 \] This simplifies to: \[ x^2 + \frac{1}{x^2} = 27 \] ### Final Answer Thus, the value of \( x^2 + \frac{1}{x^2} \) is: \[ \boxed{27} \] ---
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