x+1/x=3x²+1/x²=x²+2+1/x²-2=(x+1/x)²-2=3²-2=7x^4+1/x^4=x^4+2+1/x^4-2=(x²+1/x²)²-2=7²-2=47
1/2x=3x=1/61/(x2+x2)=721/(x4+x4)=2592
