Question

determinati media geometrica a numerelor:

x=a+50 si y=1a cu bara+2a cu bara+3a bara...+9a cu bara

Answer 1

[tex]x=a+50\\ y=\overline{1a}+...+\overline{9a}\\ y=10+a+20+a+...+90+a\\ y=9a+10(1+2+...+9)\\ y=9a+10\cdot \frac{10\cdot 9}{2} \\ y=9a+450\\ y=9(a+50)\\ M_g= \sqrt{x\cdot y} = \sqrt{(a+50)9(a+50)} = \sqrt{9(a+50)^2} =3(a+50)[/tex]