4. x1 verifica ecuatia data x1patrat-2008x1+1=0, x1patrat+1=2008x1
x1+1/x1=x1patrat+1/x1=2008x1/x1=2008
5. Cnluate cate 2=n!/2!(n-2)!=n(n-1)(n-2)!/2(n-2)!=(npatrat-n)/2=28
npatrat-n-56=0 cu solutiile n=8, n=-7 solutia este n=8 deoarece n numar natural
