Question

(2^3 × 12 + 2^3 × 13 +.....+ 2^3 × 100) : 2492

Answer 1

(2^3×2^12+2^3×2^13+.......+2^3×2^100):2492=
2^3(12+13+.......+.100):2349
1+2+3+....+100=100×101/2=50×101=5050
1+2+3+...+11=11×12/2=66
scăzând sumele obținem
12+13+....+100=5050-66=4984
ex devine
2^3×4984:2492=2^3×2=2^4=16