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If x+y=6 and xy =2find x³+y³(please help me fast with explanation also please) T^T​

User Tobonaut
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1 Answer

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Answer: x³+y³=180

Step-by-step explain: let's remember the formula x³+y³=(x+y)(x²-xy+y²) and also x³+y³=(x+y)³-3xy(x+y) then
\displaystyle\boldsymbol{ x^3+y^3=\underbrace{(x+y)^3}_(6)-3\underbrace{xy}_(2)\underbrace{(x+y)}_6}=\\\\6^3-3\cdot 2\cdot 6=216-36=180

User Chris Cannon
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