Question

(7~10-7~9):(7~9-7~8)
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Answer 1

Explicație pas cu pas:

$( {7}^{10} - {7}^{9}) : ( {7}^{9} - {7}^{8}) = [{7}^{9} \cdot (7 - 1)] : [{7}^{9} \cdot (7 - 1)] =$

$= (6 \cdot {7}^{9}) : (6 \cdot {7}^{8}] = {7}^{9 - 8} = {7}^{1} = 7$