Show me the steps to solve C$$u $3$:

M$$t m$$y ph$$t si$$u cao t$$n $($Vs$,$ Rs$)$ ph$$t t$$n hi$$u $$ t$$n s$2\mathrm{.}4$ GHz ra t$$i $\backslash (75\backslash$Omega $\backslash )$ th$$ng qua m$$t $$ng d$$y truy$$n s$$ng kh$$ng t$$n hao c$$ tr$$ kh$$ng $$t t$$nh $\backslash (75\backslash$Omega $\backslash )$ nh$$ h$$nh v$2.$

a$.$ Vi$$t bi$$u th$$c $$i$$n $$p t$$i $$u $$ng d$$y v$$ cu$$i $$ng d$$y$.$ Ch$$ng gi$$ng nhau hay kh$$c nhau? V$$ sao?

b$.$ X$$c $$nh c$$ng su$$t tr$$n t$$i $\backslash (\backslash$mathrm$\{$Z$\}\_\{\backslash$mathrm$\{$L$\}\}\backslash )$ theo dBm $.$