Răspuns:
Explicație pas cu pas:
1. 2^1912(1+2+4)= 2^1912 x 5 (Factor comun pe cel mai mic)
2. 3^195(1+9+ 81)= 3^195 x 91
3. 11^2(1+11+11^2 +11^3 +11^4)= 121(12+121 +1331+14641)= 16 105
4. 13(1+13+13^2+13^3+13^4)= Calculator
5 5^1931(1+5^2+5^4+5^7)= Calculator
6. 10^(n+1) (1+10+10^2+10^3)=10^(n+1) (11 + 100 + 1000)= 10^(n+1) x 1110
7. 2^n(1+2)=3 x 2^n
8. 3^(2n) (1+3)=3^(2n) x 4
9. 11^(3n+1) (1+11)= 11^(3n+1) x 12
