Răspuns :
x+y=2√3
xy=2
x²+2xy+y²=(x+y)²=12
x²+2xy+y²=12 ⇒x²+y²=8
x⁴+2x²y²+y⁴=(x²+y²)²=64
x⁴+2x²y²+y⁴=64 ⇒x⁴+y⁴=56
xy=2
x²+2xy+y²=(x+y)²=12
x²+2xy+y²=12 ⇒x²+y²=8
x⁴+2x²y²+y⁴=(x²+y²)²=64
x⁴+2x²y²+y⁴=64 ⇒x⁴+y⁴=56