suma directa y ecuacions cúbiques

x^{3}+y^{3} = k
(1/4)·( x[+]y )^{3} = k
( x[+]y )^{3} = 4k
( x[+]y ) = 4^{(1/3)}·k^{(1/3)}


x = (2/4^{(2/3)})·k^{(1/3)}
y = (2/4^{(2/3)})·k^{(1/3)}


x^{3}+y^{3} = (x+y)
(1/4)·( x[+]y )^{3} = (x+y)
( x[+]y )^{3} = 4·(x+y)^{(1/3)}
( x[+]y ) = 4^{(1/3)}·(x+y)^{(1/3)}


x = 1
y = 1


x^{3}+y^{3} = (x+y)^{2}
(1/4)·( x[+]y )^{3} = (x+y)^{2}
( x[+]y )^{3} = 4·(x+y)^{(2/3)}
( x[+]y ) = 4^{(1/3)}·(x+y)^{(2/3)}


x = 2
y = 2