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If x+1/x = 2 then x^3 + 1/x^3

User Mike Moore
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2 Answers

3 votes

x + 1 / x = 2

x × ( x + 1 / x ) = x × 2

x + 1 = 2x

x - x + 1 = 2x - x

x = 1

_________________________________

x^3 + 1 / x^3 =

1^3 + 1 / 1^3 =

1 + 1 / 1 =

2 / 1 =

2

User Hena Shiekh
by
3.4k points
4 votes

Answer:

Let p (x) = x + 1 / x = 2

= x + 1 = 2x

= 2x - x = 1

or, x = 1.

let g(x) = x^3 + 1/x^3

since, x = 1

therefore,

g (1) = (1)^3 +1 / (1)^3

= 1 + 1 / 1

= 2 / 1

= 2

So, the answer to your question is 2.

User Dalinaum
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3.5k points