Question

Поможіть будь ласка але срочно

Answer 1

Ответ:

${7}^{9} + {7}^{8} + {7}^{7} = {7}^{2 + 7} + {7}^{1 + 7} + {7}^{7} = {7}^{2} \times {7}^{7} + 7 \times {7}^{7} + {7}^{7} = ( {7}^{2} + 7 + 1) \times {7}^{7} = (49 + 7 + 1) \times {7}^{7} = (50 + 7) \times {7}^{7} = 57 \times {7}^{7}$