Question

AJUTOR RAPID DAU COROANA

E(x)=5 (am calculat eu)​

Answer 1

Răspuns:

intr-adevar E(x)=5, ∀x∈R⇒

⇒E(n)=5, ∀n∈Z

n∈{0;±2}⊂Z

Explicație pas cu pas:

intr-adevar E(x)=5, ∀x∈R⇒

⇒E(n)=5, ∀n∈Z (vezi atasament)

e9x) =5=comstanjt

5/(n²+1)∈Z

5∈N

n²+1≥1 decim pt n∈N, n²+1∈N

cum 5/(n²+1) ∈Z⇒5/(n²+1)∈N

n²+1∈D5N={1;5}⇒n²∈{0;4}⇒n∈{0;±2}