Question

Dau coroana ex 2 si 3

Answer 1

ex2)=1997+2x(1996x1997)/2=1997+1996x1997=1997(1+1996)=1997x1997=$1997^{2}$ patrat perfect

ex3) fie n coordonatele egale
deci f(n)=n
2n+1=n
2n-n=-1
n=-1
Punctul cu coordonatele egale este A(-1,-1)