x+y=3,xy=1
å(x+y)²=9
x²+y²=9-2xy=7
x³+y³=(x+y)(x²-xy+y²)
=3[(x+y)²-3xy]
=3Ã(9-3)
=18
xçäºæ¬¡æ¹+yçäºæ¬¡æ¹
=(x²+y²)(x³+y³)-x²y³-x³y²
=7Ã18-(xy)²(x+y)
=7Ã18-3
=123
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å(x+y)²=9
x²+y²=9-2xy=7
x³+y³=(x+y)(x²-xy+y²)
=3[(x+y)²-3xy]
=3Ã(9-3)
=18
xçäºæ¬¡æ¹+yçäºæ¬¡æ¹
=(x²+y²)(x³+y³)-x²y³-x³y²
=7Ã18-(xy)²(x+y)
=7Ã18-3
=123
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