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Given-that-x-y-2-x-2-y-2-6-find-the-value-of-x-3-y-3-




Question Number 131333 by ZiYangLee last updated on 03/Feb/21
Given that    { ((x+y=2)),((x^2 +y^2 =6)) :}  find the value of x^3 +y^3 .
Giventhat{x+y=2x2+y2=6findthevalueofx3+y3.
Answered by mr W last updated on 03/Feb/21
x^2 +y^2 =(x+y)^2 −2xy  6=2^2 −2xy  ⇒xy=−1    x^3 +y^3 =(x+y)^3 −3xy(x+y)  =2^3 −3(−1)(2)  =14
x2+y2=(x+y)22xy6=222xyxy=1x3+y3=(x+y)33xy(x+y)=233(1)(2)=14