Question

me ajudem por favor urgente ​

Answer 1

Explicação passo-a-passo:

$3)a) \frac{1}{ {7}^{5} } = {7}^{ - 5} \\ \\ b) \frac{1}{ {10}^{9} } = {10}^{ - 9} \\ \\ c) \frac{1}{ {5}^{6} } = {5}^{ - 6} \\ \\ d) \frac{1}{ {2}^{10} } = {2}^{ - 10}$

$4)x = ( {2}^{0} + {2}^{ - 1} ) \div ( {2}^{0} - {2}^{ - 1} ) \\ \\ x = (1 + \frac{1}{2} ) \div (1 - \frac{1}{2} ) \\ \\ x = ( \frac{(2 \times 1) + 1}{2} ) \div ( \frac{(2 \times 1) - 1}{2} ) \\ \\ x = ( \frac{2 + 1}{2} ) \div ( \frac{2 - 1}{2} ) \\ \\ x = \frac{3}{2} \div \frac{1}{2} \\ \\ x = \frac{3}{2} \times 2 \\ \\ x = 3$