Question

$\small \rm \red{If \: (1 + x + {x}^{2} ) ^{n} = a_{0} + a_{1}x + a_{2} {x}^{2} ... + a_{2n} {x}^{2n} } \\ \rm \red{then \: find \: a_{0} ^{2} - {a_{1}}^{2} + {a_{2}}^{2} - {a_{3}}^{2} + ...}$​

Answer 1

Refer above attachment.

$\sf \: Answer \: : S = a_{n}$