Question

DETERMINATI U(n)
b) 2la puterea n + 3 la puterea n + 7 la puterea n + 8 la puterea n

Answer 1

pt n=4k , U(a^n)=U(a^4)
U(2^n)=6, U(3^n)=1, U(7^n)=1, U(8^n)=6
U(x)=6+1+1+6=U(14)=4

pt n= 4k+1 , U(a^n)=U(a)
U(2^n)=2, U(3^n)=3, U(7^n)=7, U(8^n)=8
U(x)=2+3+7+8=0

pt n=4K+2, U (a^n)=U(a^2)
U(2^2)=4, U(3^2)=9, U(7^2)=9, U(8^2)=4
U(x)=U(4+9+9+4)=U(26)=6

pt n=4k+3, U(a^n)=U(a^3)
U(2^3)=8, U(3^3)=7, U(7^3)=3, U(8^3)=2
U(x)=0