User:ZyMOS/temp/text-test

$$ \iint_{D}^{W} \, dx\,dy $$

$$ x^n $$

$$ L=\frac{\mu A_c n^2}{l} $$

$$ \frac{V_1}{V_2}=\frac{n_1}{n_2} $$

$$ \frac{I_1}{I_2}=\frac{n_2}{n_1} $$