Question

Stiind ca a-1/a=5 , calculeaza a^2+1/a^2 , a diferit de 0 .

Answer 1

[tex]\displaystyle a- \frac{1}{a} =5\\ (a- \frac{1}{a})^2 =5^2\\ a^2-2+ \frac{1}{a^2} =25\\ a^2+ \frac{1}{a^2} =25+2=27[/tex]