Question

Найдите значение выражения.

Answer 1

$frac{ sqrt{(392-388)(392+388)} }{ sqrt{5*39} } =frac{ sqrt{(4)(780)} }{ sqrt{5*39} } =frac{ sqrt{(4)(39*2*10)} }{ sqrt{5*39} } = sqrt{4*2*2} =4$

Answer 2

|392^2-388^2 /. |195=
=|(392-388)(392+388) / |195=
=|4*780 / |195=2|780/ |195=
=2|780:195=2|4=2*2=4