Question

Вычислите:
7^-7*7^-4/7^-13

Answer 1

$\frac{ 7^{-7} * 7^{-4} }{ 7^{-13} } = \frac{ 7^{-11} }{ 7^{-13} } =7^2=49$

Answer 2

$x^a*x^b=x^{a+b} \\ \frac{x^a}{x^b} =x^{a-b} \\ \\ \frac{7^{-7}*7^{-4}}{7^{-13}} = \frac{7^{-7+(-4)}}{7^{-13}} =\frac{7^{-7-4}}{7^{-13}} =\frac{7^{-11}}{7^{-13}} =7^{-11-(-13)}=7^{-11+13}=7^2=49$