v 6.16

\sqrt{T} \propto E (x) = \frac{E_{0}}{b} (1 - \cos (\frac{2 π x}{b}))

${\sqrt{T} \varpropto E(x) = \frac{E_0}{b} \bigg(1 - \cos \bigg(\frac{2 \pi x}{b}\bigg)\bigg)}$

Error