Question

aratati ca urmatoarele numere nu sunt patrate perfecte studiing ultima cifra 2 la puterea 403 plus 2 la puterea 402

Answer 1

$2^{403} + 2^{402} =2^{402}(2+1)=2^{402}*3=(2^4)^{100}*2^2*3=16^{100}*12$
$U\left \{ {16^{100}*12}\right \}=U\left \{ {16^{100}}\right \}*U\left \{ 12\right \}=U\left \{ 6*2\right \}=2$