Question

Determinat ultima cifra a numarului A=2^31+3^42.Urgent va rog.!!!!!!!!!!!!!!!!!!. Dau coroana+ma abonez

Answer 1

u(2¹) = 2 ; u(2²)=4 ; u(2³)=8 u(2⁴)=4  de aici incepe  repatitia

=> u(2³¹)=u(2⁴ˣ⁷)*u(2³)=u(4*8)=2 ;

u(3¹)=3 ; u(3²)=9 ; u(3³)7 si u(3⁴)=1     incepe repetitia

=> u(3⁴²)=u(3⁴ˣ¹⁰⁺²)=u(1*9)=9

=>      u(A) = u(2*9)= 8