If X3 + Y3 = 9 and X + Y = 3, Find Xy. - Mathematics

If x³ + y³ = 9 and x + y = 3, find xy.

Sum

x³ + y³ = 9, x + y = 3
(x + y)³ = x³+ y³+ 3xy (x + y)
⇒ (3)³ = 9 + 3xy (3)
⇒ 27 = 9 + 9xy
⇒ 9xy = 27 - 9 = 18
⇒ xy = 2.

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