Answer:
[tex]\large\boxed{0.00003400=3.4\cdot10^{-4}}[/tex]
Step-by-step explanation:
The scientific notation:
[tex]a\cdot 10^k[/tex]
where
[tex]1\leq a<10,\ k\in\mathbb{Z}[/tex]
[tex]0.0003400=0\underbrace{.0003}_{4\to}4=3.4\cdot10^{-4}\\\\0.00034=3.4:10000=3.4:10^4=3.4\cdot\dfrac{1}{10^4}=3.4\cdot10^{-4}\\\\\text{used}\ a^{-n}=\dfrac{1}{a^n}[/tex]
