Question

Помогите пожалуйста.
1) 3^5+3^9/3^-5+3^-9
2) 2^5+2^6+2^7/2^-5+2^-6+2^-7
(^) - степень
(/) - дробь

Answer 1

$\frac{3^5+3^9}{3^{-5}+3^{-9}} = \frac{3^5+3^9}{ \frac{1}{ {3}^{5} } + \frac{1}{ {3}^{9} } } = \\ = \frac{ {3}^{5} + {3}^{9} }{ \frac{{3}^{5} + {3}^{9}}{{3}^{5} \cdot {3}^{9}} } = {3}^{5} \cdot {3}^{9} = \\ = {3}^{14} = 4782969$
$\frac{ {2}^{5} + {2}^{6} + {2}^{7} }{ {2}^{ - 5} +{2}^{ - 6} + {2}^{ - 7}} = \frac{ {2}^{5}(1 + 2 + {2}^{2} ) }{\frac{1}{ {2}^{7} } ( {2}^{2} + 2 + 1) } = \\ = {2}^{5} \cdot {2}^{7} = {2}^{12} = 4096$