Question

Посчитай 1⋅1!+2⋅2!+...+10⋅10!​

Answer 1

Ответ:

$1×1+2×2+...+10×10 = 1×1+2×2+3 \times 3 + 4 \times 4 + 5 \times 5 + 6 \times 6 + 7 \times 7 + 8 \times 8 + 9 \times 9+10×10 = 1 + 4 + 9 + 16 + 25 + 36 + 49 + 64 + 81 + 100 = 385$