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If (X2 + 1/x2) = 6, then find the value of (10x – 10/x)
- A± 15
- B± 20
- C± 30
- D± 40
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CCommunity
(X2 + 1/x2) = 6
⇒ (100X2 + 100/x2) = 600
⇒ (100X2 + 100/x2) – 200 = 400
⇒ (10X – 10/x)2 = 400
∴ (10X – 10/x) = ± 20
⇒ (100X2 + 100/x2) = 600
⇒ (100X2 + 100/x2) – 200 = 400
⇒ (10X – 10/x)2 = 400
∴ (10X – 10/x) = ± 20