Question

Va rog repede!!Urgent

Answer 1

intai aduni numerele si le asociezi astfel: primul termen al lui a cu primul termen al lui b, al doilea termen al lui a cu al doilea termen al lui b etc.
a+b=1/11 + 10/11 + 1/12 + 11/12 + ... + 1/2000 + 1999/2000 = 11/11 + 12/12 + ... + 2000/2000 = 1 + 1 + ... + 1 = 1990 (2000-10 termeni in fiecare).
finalizezi: media aritmetica (a+b)/2 = 1990/2 = 995

Answer 2

[tex]\text{Media aritmetica a doua numere este semisuma acelor numere.}\\ \text{Altfel spus:}m_{a,b}=\dfrac{a+b}{2}\\ \text{Pnetru exercitiul de fata vom avea:}\\ m_{a,b}=\dfrac{\dfrac{1}{11}+\dfrac{1}{12}+_{\dots}+\dfrac{1}{2000}+\dfrac{10}{11}+\dfrac{11}{12}+_{\dots}+\dfrac{1999}{2000}}{2}\\ m_{a,b}=\dfrac{\left(\dfrac{1}{11}+\dfrac{10}{11}\right)+\left(\dfrac{1}{12}+\dfrac{11}{12}\right)+_{\dots}+\left(\dfrac{1}{2000}+\dfrac{1999}{2000}\right)}{2}\\ [/tex]
[tex]~~~~~~~~~~~~~de\ 1990\ ori\\ m_{a,b}=\dfrac{\overbrace{1+1+1+1+1}}{2}\\ m_{a,b}=\dfrac{1990}{2}=\boxed{995}[/tex]