Harison ,
[tex3]9\text{ . }10^9\text{ . }\frac{\text{Q}^2}{4.(1,2)^2}=\frac{3}{4}\text{ . }0,3\text{ . }10^{-3}\text{ . }10[/tex3]
Vamos começar simplificando o que pudermos:
[tex3]\cancel{9}^{3}\text{ . }10^9\text{ . }\frac{\text{Q}^2}{\cancel{4}^1.(1,2)^2}=\frac{\cancel{3}^1}{\cancel{4}^1}\text{ . }\cancel{0,3\text{ . }10^{-3}\text{ . }10}^{3.10^{-3}}[/tex3]
[tex3]\cancel{3}^1\text{ . }10^9\text{ . }\frac{\text{Q}^2}{1,44}=\cancel{3}^1\text{ . }10^{-3}[/tex3]
[tex3]\text{Q}^2=\frac{10^{-3}\text{ . }1,44}{10^9}[/tex3]
[tex3]\text{Q}^2=1,44\text{ . }10^{-3}\text{ . }10^{-9}[/tex3]
[tex3]\text{Q}^2=1,44\text{ . }10^{-12}[/tex3]
[tex3]\text{Q}=\sqrt{1,44\text{ . }10^{-12}}[/tex3]
[tex3]\text{Q}=\sqrt{1,44}\text{ . }\sqrt{10^{-12}}[/tex3]
[tex3]\boxed{\text{Q}=1,2\text{ . }10^{-6}}[/tex3]