Question

ex 3 va rog dau coronita​

Answer 1

Explicație pas cu pas:

C) (8951-3):4+1=2013

Answer 2

$\it a)\ \ 3,\ 7,\ 11,\ 15,\ 19,\ 23,\ 27,\ ...\\ \\ b)\\ \\ a_1=3+4\cdot0\\a_2=3+4\cdot1\\a_3=3+4\cdot2\\a_4=3+4\cdot3\\.\\.\\.\\a_n=3+4\cdot(n-1)\\ \\ a_{20}=3+4\cdot19\\ \\ c)\\ \\ a_n=3+4\cdot(n-1)=2851|_{-3} \Rightarrow 4\cdot(n-1)=2848|_{:4} \Rightarrow n-1=712|_{+1} \Rightarrow \\ \\ \Rightarrow n=713\\ \\ Deci,\ \ a_{713}=2851$