Nr. complexe

Adriana Nistor · Post by **Adriana Nistor** » Mon Apr 20, 2009 6:35 pm

Se considera ecuatia \( x=(2-\frac{x+1}{x-7})^2 \), \( x\in R-\{7\} \). Rezolvati ecuatia in multimea numerelor complexe stiind ca admite solutia \( z=3+4i \).

Post by **Laurian Filip** » Tue Apr 21, 2009 1:42 pm

Observam ca \( x=9 \) este o solutie a ecuatiei.

Cum un polinom de gradul 3 are exact 3 radacini, si daca un numar complex e radacina atunci si conjugatul lui e radacina, \( S=\lbrace 9, 3+4i,3-4i \rbrace \).