Question

mim ajuda aii pro favar​

Answer 1

Vou lembrar uns conceitos:

$a {}^{b} \times a {}^{c} = a {}^{b + c} \\ \\ a {}^{b} \div a {}^{c} = a {}^{b - c}$

Agora a questão:

$20) \: \: a) \: \: \: 5 {}^{4} \div 5 {}^{2} = 5 {}^{4 - 2} = 5 {}^{2} \\ \\ b) \: \: 8 {}^{7} \div 8 {}^{3} = 8 {}^{4} \\ \\ c) \: \: 9 {}^{5} \div 9 {}^{2} = 9 {}^{3} \\ \\ d) \: \: 4 {}^{3} \div 4 {}^{2} = 4 {}^{1}$

$e) \: \: 9 {}^{6} \div 9 {}^{ 3 } = 9 {}^{3}$

$21) \: \: a) \: \: 4 {}^{3} \times 4 {}^{2} = 4 {}^{5} \\ \\ b) \: 7 {}^{4} \times 7 {}^{5} = 7 {}^{9}$

$c) \: 2 {}^{6} \times 2 {}^{2} = 2 {}^{8} \\ \\ d) \: \: 6 {}^{3} \times 6 = 6 {}^{4} \\ \\ e) \: \: 3 {}^{7} \times 3 {}^{2} = 3 {}^{9}$

$22) \: \: a) \: \: \sqrt{ \frac{144}{81} } = \frac{12}{9} = \frac{4}{ 3} \\ \\ b) \: \: \sqrt{ \frac{36}{225} } = \frac{6}{15} = \frac{2}{5}$