Ответ: =3

Объяснение:

sin(π/4)=√2/2 =>√2sin(π/4)=2/2=1

cos(-π/4)=cos(π/4)= √2/2 =>√2cos(-π/4)=2/2=1

3tg45°=3

=>√2 sin π/4 -√2 cos( -π/4) + 3tg45° =1-1+3=3