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Determine the value of x2 + y2 when x3 - y3 = 54, x - y = 18 and xy = 2

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Determine the value of x2 + y2 when x3 - y3 = 54, x - y = 18 and xy = 2
1). 0
2). 1
3). 2
4). 3


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Answered by on | Votes 0 |

Given, x3 - y3 = 54, x - y = 18 & xy = 2

As we know, x3 - y3 = (x - y) (x2 + y2 + xy)

⇒ 54 = 18 × (x2 + y2 + 2)

⇒ 3 = x2 + y2 + 2

∴ x2 + y2 = 1

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