Question

Need help.
checking invariant.

Answer 1

ARE
\[\frac{ \partial^2 E_i }{ \partial x^2 } = \frac{ \partial^2 E_i }{ \partial x'^2 } \]
and
\[\frac{ \partial E_i }{\partial t^2 } = \frac{ \partial^2 E_i }{ \partial t^2 }\]
?????
WHERE
\(x'=\frac{ 1 }{ \sqrt{1-\frac{ v^2 }{ c^2 }} } (x-vt)\) and \[t' = \frac{ 1 }{ \sqrt{1-\frac{ v^2 }{ c^2 }} } (t-\frac{ v }{ c^2 }x)\]