Question

Să se afle ultima cifră a numerelor: 2¹⁵¹⁶+8³⁰¹+7²⁰²​

Answer 1

u(2¹⁵¹⁶)=> 1516=4k=4×379

u(2¹⁵¹⁶)=6

u(8³⁰¹)=> 301=4k+1=4×75+1

u(8³⁰¹)=8

u(7²⁰²)=> 202=4k+2=4×50+2

u(7²⁰²)=9

=> u(6+8+9)=u(23)=3